Citations
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This panel provides information on past usage of this interatomic potential (IP) powered by the OpenKIM Deep Citation framework. The word cloud indicates typical applications of the potential. The bar chart shows citations per year of this IP (bars are divided into articles that used the IP (green) and those that did not (blue)). The complete list of articles that cited this IP is provided below along with the Deep Citation determination on usage. See the Deep Citation documentation for more information.
319 Citations (252 used)
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USED (definite) M. Ma’zdziarz, J. Rojek, and S. Nosewicz, “Molecular dynamics study of self-diffusion in stoichiometric B2-NiAl crystals,” Philosophical Magazine. 2018. link Times cited: 5 Abstract: ABSTRACT Self-diffusion parameters in stoichiometric B2-NiAl… read moreAbstract: ABSTRACT Self-diffusion parameters in stoichiometric B2-NiAl solid state crystals were estimated by molecular statics/dynamics simulations with the study of required simulation time to stabilise diffusivity results. An extrapolation procedure to improve the diffusion simulation results was proposed. Calculations of volume diffusivity for the B2 type NiAl in the 1224–1699 K temperature range were performed using the embedded-atom-model potential. The results obtained here are in much better agreement with the experimental results than the theoretical estimates obtained with other methods. read less USED (definite) H. Song, Y. Sun, F. Zhang, C. Wang, K. Ho, and M. Mendelev, “Nucleation of stoichiometric compounds from liquid: Role of the kinetic factor,” Physical Review Materials. 2017. link Times cited: 21 Abstract: While the role of the free energy barrier during nucleation … read moreAbstract: While the role of the free energy barrier during nucleation is a text-book subject the importance of the kinetic factor is frequently underestimated. We obtained both quantities from molecular dynamics (MD) simulations for the pure Ni and B2 phases in the Ni50Al50 and Cu50Zr50 alloys. The free-energy barrier was found to be higher in Ni but the nucleation rate is much lower in the Ni50Al50 alloy which was attributed to the ordered nature of the B2 phase. Since the Cu50Zr50 B2 phase can has even smaller fraction of the anti-site defects its nucleation is never observed in the MD simulation. read less USED (definite) “M ay 2 01 8 A Molecular Dynamics Study of Self-Diffusion in Stoichiometric B 2-NiAl crystals.” 2018. link Times cited: 0 Abstract: Self-diffusion parameters in stoichiometric B2-NiAl solid st… read moreAbstract: Self-diffusion parameters in stoichiometric B2-NiAl solid state crystals were estimated by molecular statics/dynamics simulations with the study of required simulation time to stabilise diffusivity results. An extrapolation procedure to improve the diffusion simulation results was proposed. Calculations of volume diffusivity for the B2 type NiAl in the 1224 K to 1699 K temperature range were performed using the embedded atom model potential. The results obtained here are in much better agreement with the experimental results than the theoretical estimates obtained with other methods. PACS numbers: 02.70.Ns, 66.30.h, 66.30.Fq read less USED (high confidence) I. Chesser, R. K. Koju, A. Vellore, and Y. Mishin, “Atomistic modeling of metal-nonmetal interphase boundary diffusion,” Acta Materialia. 2023. link Times cited: 0 USED (high confidence) G. Poletaev, Y. Bebikhov, A. Semenov, and R. Rakitin, “Interaction of an edge dislocation with a 〈110〉 tilt boundary in nickel: molecular dynamics simulation,” Letters on Materials. 2022. link Times cited: 1 USED (high confidence) Q. Bizot, O. Politano, V. Turlo, and F. Baras, “Molecular dynamics simulations of nanoscale solidification in the context of Ni additive manufacturing,” Materialia. 2022. link Times cited: 2 USED (high confidence) B. Shang, N. Jakse, P. Guan, W. Wang, and J. Barrat, “Influence of Oscillatory Shear on Nucleation in Metallic Glasses: A Molecular Dynamics Study,” SSRN Electronic Journal. 2022. link Times cited: 2 Abstract: The process of crystal nucleation can be accelerated or reta… read moreAbstract: The process of crystal nucleation can be accelerated or retarded by ultrasonic vibration, which is particularly attractive for the addictive manufacture and thermoplastic forming of metallic glasses, however, the effect and mechanism of oscillatory loading on the nucleation process are still elusive. By using molecular dynamics simulation, the changes in the time-temperature-transformation (TTT) curve under oscillatory external loading are systematically investigated in two typical binary alloys. A glass forming ability dependent response to the external loading is found, and the shortest incubation time is insensitive to the external loading, while the corresponding temperature can be significantly shifted. Within the framework of classical nucleation theory, a fitting formula is proposed to describe the simulation data quantitatively. In contrast to stationary shear, the elastic stress, rather than the strain rate, is the key parameter to control the evolution of TTT curve under oscillatory loading. Furthermore, the model shows that oscillatory loading can decouple the mobility and nucleation in the deeply supercooled liquid, hence the formation ability can be enhanced while the nucleation is suppressed, which is particularly helpful for the forming and manufacturing of metallic glasses. read less USED (high confidence) C. Li et al., “Ultrafast modulation of the molten metal surface tension under femtosecond laser irradiation,” Chinese Physics Letters. 2022. link Times cited: 1 Abstract:
We predict ultrafast modulation of the pure molten metal s… read moreAbstract:
We predict ultrafast modulation of the pure molten metal surface stress fields under the irradiation of the single femtosecond laser pulse through the two-temperature model molecular-dynamics simulations. High-resolution and precision calculations are used to resolve the ultrafast laser-induced anisotropic relaxations of the pressure components on the time-scale comparable to the intrinsic liquid density relaxation time. The magnitudes of the dynamic surface tensions are found being modulated sharply within picoseconds after the irradiation, due to the development of the nanometer scale non-hydrostatic regime behind the exterior atomic layer of the liquid surfaces. The reported novel regulation mechanism of the liquid surface stress field and the dynamic surface tension hints at levitating the manipulation of liquid surfaces, such as ultrafast steering the surface directional transport and patterning. read less USED (high confidence) Y. Nagatsuma, M. Ohno, T. Takaki, and Y. Shibuta, “Bayesian Data Assimilation of Temperature Dependence of Solid–Liquid Interfacial Properties of Nickel,” Nanomaterials. 2021. link Times cited: 8 Abstract: Temperature dependence of solid–liquid interfacial propertie… read moreAbstract: Temperature dependence of solid–liquid interfacial properties during crystal growth in nickel was investigated by ensemble Kalman filter (EnKF)-based data assimilation, in which the phase-field simulation was combined with atomic configurations of molecular dynamics (MD) simulation. Negative temperature dependence was found in the solid–liquid interfacial energy, the kinetic coefficient, and their anisotropy parameters from simultaneous estimation of four parameters. On the other hand, it is difficult to obtain a concrete value for the anisotropy parameter of solid–liquid interfacial energy since this factor is less influential for the MD simulation of crystal growth at high undercooling temperatures. The present study is significant in shedding light on the high potential of Bayesian data assimilation as a novel methodology of parameter estimation of practical materials an out of equilibrium condition. read less USED (high confidence) K. Ferasat, T. Swinburne, P. Saidi, M. Daymond, Z. Yao, and L. K. B’eland, “Interstitialcy-based reordering kinetics of Ni_3Al precipitates in irradiated Ni-based super alloys.” 2021. link Times cited: 0 USED (high confidence) Y.-S. Lin, G. P. P. Pun, and Y. Mishin, “Development of a physically-informed neural network interatomic potential for tantalum,” Computational Materials Science. 2021. link Times cited: 9 USED (high confidence) O. Politano and F. Baras, “Reaction front propagation in nanocrystalline Ni/Al composites: A molecular dynamics study,” Journal of Applied Physics. 2020. link Times cited: 10 Abstract: This work focuses on a class of nano-laminated Ni/Al composi… read moreAbstract: This work focuses on a class of nano-laminated Ni/Al composites fabricated by a rolling-stacking procedure. This method results in nano-laminated composites with a complex structure. Their reactivity was compared with that of reactive multilayer nanofoils with constant bilayer thickness. Typical samples are composed of randomly distributed grains of Ni and Al. The self-propagating reactive front presents peculiarities that are directly related to the initial microstructure. The combustion mode is unsteady, with shifts in velocity. The temperature profile is characterized by broad combustion and post-combustion zones. The instantaneous shape of the front is tortuous, with the appearance of hot spots correlated with the underlying grain configuration. Local dynamics was studied in order to detect all the elemental processes occurring at nanoscale that trigger propagation: melting of Al, coarsening of Al grains, progressive exothermic dissolution mixing, heterogeneous nucleation, and growth of the intermetallic phase, B2-NiAl. The role of the complex initial microstructure was clearly demonstrated. read less USED (high confidence) J. Ding et al., “The Effects of Grain Boundary Misorientation on the Mechanical Properties and Mechanism of Plastic Deformation of Ni/Ni3Al: A Molecular Dynamics Study,” Materials. 2020. link Times cited: 3 Abstract: The effects of grain boundary misorientation angle (θ) on me… read moreAbstract: The effects of grain boundary misorientation angle (θ) on mechanical properties and the mechanism of plastic deformation of the Ni/Ni3Al interface under tensile loading were investigated using molecular dynamics simulations. The results show that the space lattice arrangement at the interface is dependent on grain boundary misorientations, while the interfacial energy is dependent on the arrangement. The interfacial energy varies in a W pattern as the grain boundary misorientation increases from 0° to 90°. Specifically, the interfacial energy first decreases and then increases in both segments of 0–60° and 60–90°. The yield strength, elastic modulus, and mean flow stress decrease as the interfacial energy increases. The mechanism of plastic deformation varies as the grain boundary misorientation angle (θ) increases from 0° to 90°. When θ = 0°, the microscopic plastic deformation mechanisms of the Ni and Ni3Al layers are both dominated by stacking faults induced by Shockley dislocations. When θ = 30°, 60°, and 80°, the mechanisms of plastic deformation of the Ni and Ni3Al layers are the decomposition of stacking faults into twin grain boundaries caused by extended dislocations and the proliferation of stacking faults, respectively. When θ = 90°, the mechanisms of plastic deformation of both the Ni and Ni3Al layers are dominated by twinning area growth resulting from extended dislocations. read less USED (high confidence) N. Lopanitsyna, C. B. Mahmoud, and M. Ceriotti, “Finite-temperature materials modeling from the quantum nuclei to the hot electron regime,” arXiv: Materials Science. 2020. link Times cited: 13 Abstract: Atomistic simulations provide insights into structure-proper… read moreAbstract: Atomistic simulations provide insights into structure-property relations on an atomic size and length scale, that are complementary to the macroscopic observables that can be obtained from experiments. Quantitative predictions, however, are usually hindered by the need to strike a balance between the accuracy of the calculation of the interatomic potential and the modelling of realistic thermodynamic conditions. Machine-learning techniques make it possible to efficiently approximate the outcome of accurate electronic-structure calculations, that can therefore be combined with extensive thermodynamic sampling. We take elemental nickel as a prototypical material, whose alloys have applications from cryogenic temperatures up to close to their melting point, and use it to demonstrate how a combination of machine-learning models of electronic properties and statistical sampling methods makes it possible to compute accurate finite-temperature properties at an affordable cost. We demonstrate the calculation of a broad array of bulk, interfacial and defect properties over a temperature range from 100 to 2500 K, modeling also, when needed, the impact of nuclear quantum fluctuations and electronic entropy. The framework we demonstrate here can be easily generalized to more complex alloys and different classes of materials. read less USED (high confidence) M. Wagih, P. M. Larsen, and C. Schuh, “Learning grain boundary segregation energy spectra in polycrystals,” Nature Communications. 2020. link Times cited: 62 USED (high confidence) G. P. P. Pun, V. Yamakov, J. Hickman, E. Glaessgen, and Y. Mishin, “Development of a general-purpose machine-learning interatomic potential for aluminum by the physically informed neural network method,” Physical Review Materials. 2020. link Times cited: 13 Abstract: Interatomic potentials constitute the key component of large… read moreAbstract: Interatomic potentials constitute the key component of large-scale atomistic simulations of materials. The recently proposed physically-informed neural network (PINN) method combines a high-dimensional regression implemented by an artificial neural network with a physics-based bond-order interatomic potential applicable to both metals and nonmetals. In this paper, we present a modified version of the PINN method that accelerates the potential training process and further improves the transferability of PINN potentials to unknown atomic environments. As an application, a modified PINN potential for Al has been developed by training on a large database of electronic structure calculations. The potential reproduces the reference first-principles energies within 2.6 meV per atom and accurately predicts a wide spectrum of physical properties of Al. Such properties include, but are not limited to, lattice dynamics, thermal expansion, energies of point and extended defects, the melting temperature, the structure and dynamic properties of liquid Al, the surface tensions of the liquid surface and the solid-liquid interface, and the nucleation and growth of a grain boundary crack. Computational efficiency of PINN potentials is also discussed. read less USED (high confidence) J. Amodeo, F. Pietrucci, and J. Lam, “Out-of-Equilibrium Polymorph Selection in Nanoparticle Freezing.,” The journal of physical chemistry letters. 2020. link Times cited: 7 Abstract: The ability to design synthesis processes that are out of eq… read moreAbstract: The ability to design synthesis processes that are out of equilibrium has opened the possibility of creating nanomaterials with remarkable physico-chemical properties, choosing from a much richer palette of possible atomic architectures compared to equilibrium processes in extended systems. In this work, we employ atomistic simulations to demonstrate how to control polymorph selection via cooling rate during nanoparticle freezing in the case of Ni$_3$Al, a material with a rich structural landscape. State-of-the-art free-energy calculations allow to rationalize the complex nucleation process, discovering a switch between two kinetic pathways, yielding the equilibrium structure at room temperature and an alternative metastable one at higher temperature. Our findings address the key challenge in the synthesis of nano-alloys for technological applications, i.e., rationally exploiting the competition between kinetics and thermodynamics by designing a treatment history that forces the system into desirable metastable states. read less USED (high confidence) S. Gowthaman and T. Jagadeesha, “Effect of Point Defects on the Tensile and Thermal Characteristics of Nickel–Aluminum Nanowire through Molecular Dynamics,” Transactions of the Indian Institute of Metals. 2020. link Times cited: 11 USED (high confidence) B. Chen, W. Wu, and M. Chen, “Orientation-Dependent Morphology and Evolution of Interfacial Dislocation Networks in Ni-Based Single-Crystal Superalloys: A Molecular Dynamics Simulation,” Acta Mechanica Solida Sinica. 2020. link Times cited: 5 USED (high confidence) B. Chen, W. Wu, and M. Chen, “Orientation-Dependent Morphology and Evolution of Interfacial Dislocation Networks in Ni-Based Single-Crystal Superalloys: A Molecular Dynamics Simulation,” Acta Mechanica Solida Sinica. 2020. link Times cited: 0 USED (high confidence) S. O. Kart, H. H. Kart, and T. Çagin, “Atomic-scale insights into structural and thermodynamic stability of spherical Al@Ni and Ni@Al core–shell nanoparticles,” Journal of Nanoparticle Research. 2020. link Times cited: 6 USED (high confidence) Y. Liang, G. D. Leines, R. Drautz, and J. Rogal, “Identification of a multi-dimensional reaction coordinate for crystal nucleation in Ni3Al.,” The Journal of chemical physics. 2020. link Times cited: 10 Abstract: Nucleation during solidification in multi-component alloys i… read moreAbstract: Nucleation during solidification in multi-component alloys is a complex process that comprises competition between different crystalline phases as well as chemical composition and ordering. Here, we combine transition interface sampling with an extensive committor analysis to investigate the atomistic mechanisms during the initial stages of nucleation in Ni3Al. The formation and growth of crystalline clusters from the melt are strongly influenced by the interplay between three descriptors: the size, crystallinity, and chemical short-range order of the emerging nuclei. We demonstrate that it is essential to include all three features in a multi-dimensional reaction coordinate to correctly describe the nucleation mechanism, where, in particular, the chemical short-range order plays a crucial role in the stability of small clusters. The necessity of identifying multi-dimensional reaction coordinates is expected to be of key importance for the atomistic characterization of nucleation processes in complex, multi-component systems. read less USED (high confidence) B. Witbeck and D. Spearot, “Role of grain boundary structure on diffusion and dissolution during Ni/Al nanolaminate combustion,” Journal of Applied Physics. 2020. link Times cited: 13 Abstract: Ni/Al nanolaminates are reactive materials with customizable… read moreAbstract: Ni/Al nanolaminates are reactive materials with customizable combustion characteristics. A common approach to synthesize the repeating Ni and Al nanolayers is physical vapor deposition, which often results in columnar grains with ⟨ 111 ⟩ texture and grain diameters on the order of a single layer thickness. Changes in grain size have been reported to affect combustion rates, yet the role of individual grain boundaries (GBs) on this process is unclear. Thus, this work investigates the role of the GB structure on atomic diffusion/dissolution and the resulting combustion reaction via molecular dynamics simulations. Nanolaminate combustion is simulated in bicrystal models containing columnar symmetric tilt GBs with ⟨ 111 ⟩ misorientation axis perpendicular to the Ni/Al interface. A range of GB misorientation angles is studied, and combustion in a Ni/Al nanolaminate without GBs is simulated for comparison. Combustion in bicrystal models reveals a rise in temperature with an exponential form prior to complete Al melting, while the model without GBs shows a linear temperature increase. Diffusion coefficients are measured for each bicrystal model, and separate Arrhenius fits are used to identify the first three combustion stages. Models containing higher energy GBs generally have higher diffusion coefficients and lower activation energies prior to complete melting of Al, while the GB structure shows little effect on dissolution after the Al layer melts. Thus, the GB structure plays a key role in Ni/Al nanolaminate ignition sensitivity but does not impact runaway combustion. read less USED (high confidence) Q. Cao, P.-P. Wang, and D.-hui Huang, “Revisiting the Stokes-Einstein relation for glass-forming melts.,” Physical chemistry chemical physics : PCCP. 2020. link Times cited: 6 Abstract: Molecular dynamics simulations of Ni36Zr64, Cu65Zr35 and Ni8… read moreAbstract: Molecular dynamics simulations of Ni36Zr64, Cu65Zr35 and Ni80Al20 were carried out over a broad range of temperature (900-3000 K) to investigate the Stokes-Einstein (SE) relation for glass-forming melts. Our results reproduce experimental structural and transport properties. Results show that the breakdown temperature of the SE relation (TSE) equals the dynamical crossover temperature (TA) and both are roughly twice the glass-transition temperature (Tg) for the three glass-forming melts (TSE = TA ≈ 2.0Tg). The product of the individual component self-diffusion coefficient and viscosity Dαη can be roughly regarded as a constant at the transition zone (a small temperature range around TSE) in which the temperature behaviors of self-diffusion coefficient and viscosity switch from high-temperature Arrhenius to a low-temperature VFT behavior. Below TSE, the decoupling of component diffusion coefficients was found. In particular, the decoupling of component diffusion coefficients can be ascribed to the decoupling of the partial pair structural correlation of components, which can be clearly reflected by the intersection of the high-temperature and low-temperature behaviors of the ratio between the partial pair correlation entropy of components (Sβ2/Sα2). Furthermore, the ratio between the partial pair correlation entropy of components may be used to predict the validity of the SE relation, in the absence of both transport coefficients and atomic coordinates. read less USED (high confidence) J. Alizadeh, M. Panjepour, and M. Ahmadian, “Modeling the Stretch Behavior of the Single-Crystal Ni–Al Alloy and Its Molecular Dynamics Simulation,” Physics of the Solid State. 2020. link Times cited: 3 USED (high confidence) R. Webler et al., “On the influence of Al-concentration on the fracture toughness of NiAl: microcantilever fracture tests and atomistic simulations,” Acta Materialia. 2019. link Times cited: 3 USED (high confidence) L. Karkina, I. Karkin, A. Kuznetsov, and Y. Gornostyrev, “Alloying Element Segregation and Grain Boundary Reconstruction, Atomistic Modeling.” 2019. link Times cited: 8 Abstract: Grain boundary (GB) segregation is an important phenomenon t… read moreAbstract: Grain boundary (GB) segregation is an important phenomenon that affects many physical properties, as well as microstructure of polycrystals. The segregation of solute atoms on GBs and its effect on GB structure in Al were investigated using two approaches: First principles total energy calculations and the finite temperature large-scale atomistic modeling within hybrid MD/MC approach comprising molecular dynamics and Monte Carlo simulations. We show that the character of chemical bonding is essential in the solute–GB interaction, and that formation of directed quasi-covalent bonds between Si and Zn solutes and neighboring Al atoms causes a significant reconstruction of the GB structure involving a GB shear-migration coupling. For the solutes that are acceptors of electrons in the Al matrix and have a bigger atomic size (such as Mg), the preferred position is determined by the presence of extra volume at the GB and/or reduced number of the nearest neighbors; in this case, the symmetric GB keeps its structure. By using MD/MC approach, we found that GBs undergo significant structural reconstruction during segregation, which can involve the formation of singleor double-layer segregations, GB splitting, and coupled shear-migration, depending on the details of interatomic interactions. read less USED (high confidence) A. Dongare, “Challenges to model the role of heterogeneities on the shock response and spall failure of metallic materials at the mesoscales,” Journal of Materials Science. 2019. link Times cited: 11 USED (high confidence) A. R. Kuznetsov, S. Starikov, V. Sagaradze, and L. E. Kar’kina, “Deformation-Induced Dissolution of Ni3Al Particles in Nickel: Atomistic Simulation,” Physics of Metals and Metallography. 2019. link Times cited: 3 USED (high confidence) G. Wu et al., “Hierarchical nanostructured aluminum alloy with ultrahigh strength and large plasticity,” Nature Communications. 2019. link Times cited: 88 USED (high confidence) P. Zakharov, M. Starostenkov, E. Korznikova, A. Eremin, I. Lutsenko, and S. V. Dmitriev, “Excitation of Soliton-Type Waves in Crystals of the A3B Stoichiometry,” Physics of the Solid State. 2019. link Times cited: 8 USED (high confidence) Y. Xiong et al., “Molecular dynamics simulations of shock loading of nearly fully dense granular Ni-Al composites.,” Physical chemistry chemical physics : PCCP. 2019. link Times cited: 11 Abstract: We used molecular dynamics simulations to study the shock pr… read moreAbstract: We used molecular dynamics simulations to study the shock propagation, inhomogeneous deformation, and initiation of the chemical reaction characteristics of nearly fully dense reactive Ni-Al composites. For shocks with piston velocities Up ≤ 2.0 km s-1, particle velocity dispersion was observed at the shock front, which increased on increasing the shock strength. Plastic deformation mainly occurred at the grain boundaries or grain junction during the shock rise and was accompanied by the generation of a potential hot spot in the region where severe plasticity happens. The composite exhibited higher strength and lower reactivity than the mixtures with certain porosity. In addition, the shock-induced premature melting of Al led to the expansion of particle velocity dispersion from the wavefront to the shocked zone and the formation of a heterogeneous velocity field for stronger shocks beyond critical Up (2.5 km s-1). The velocity heterogeneity in the shocked region led to localized shear, strong erosion of Ni, and occurrence of ultrafast chemical reactions. Therefore, the shock-induced premature melting of Al led to the mechanochemical effect and played a role in the shock-induced chemical reaction in the reactive metal system. read less USED (high confidence) Q. Cao, F. Tu, L. Xue, and F.-hou Wang, “Assessing relationships between self-diffusion coefficient and viscosity in Ni-Al alloys based on the pair distribution function,” Journal of Applied Physics. 2019. link Times cited: 5 Abstract: Based on the pair distribution function g(r), molecular dyna… read moreAbstract: Based on the pair distribution function g(r), molecular dynamics simulations on NiAl and Ni3Al melts were carried out to investigate the relationships between self-diffusion coefficient and viscosity. The self-diffusion coefficients of Ni in melts and the viscosity of melts were calculated using the Einstein relation and Green-Kubo equation, respectively. Our result shows that there is a crossover in the self-diffusion coefficient and viscosity from high-temperature Arrhenius behavior to low-temperature non-Arrhenius behavior, and the crossover is accompanied by the breakdown of Stokes-Einstein relation (SER) and the onset of fractional Stokes-Einstein relation. The breakdown temperature of SER is nearly twice the glass-transition temperature and much higher than the mode-coupling critical temperature for both NiAl and Ni3Al melts. Further analyses based on g(r) suggest that temperature dependences of the pair correlation entropy and the partial pair correlation entropy of components may be used as probes for testing the validity of Stokes-Einstein relation and predicting its breakdown temperature.Based on the pair distribution function g(r), molecular dynamics simulations on NiAl and Ni3Al melts were carried out to investigate the relationships between self-diffusion coefficient and viscosity. The self-diffusion coefficients of Ni in melts and the viscosity of melts were calculated using the Einstein relation and Green-Kubo equation, respectively. Our result shows that there is a crossover in the self-diffusion coefficient and viscosity from high-temperature Arrhenius behavior to low-temperature non-Arrhenius behavior, and the crossover is accompanied by the breakdown of Stokes-Einstein relation (SER) and the onset of fractional Stokes-Einstein relation. The breakdown temperature of SER is nearly twice the glass-transition temperature and much higher than the mode-coupling critical temperature for both NiAl and Ni3Al melts. Further analyses based on g(r) suggest that temperature dependences of the pair correlation entropy and the partial pair correlation entropy of components may be used as probes... read less USED (high confidence) S. Nag, T. Junge, and W. Curtin, “Atomistic-continuum coupling of random alloys,” Modelling and Simulation in Materials Science and Engineering. 2019. link Times cited: 4 Abstract: Random alloys are multicomponent systems where the atomic ty… read moreAbstract: Random alloys are multicomponent systems where the atomic type on each lattice site is independent of the atom types on any other lattice site. The fluctuations in local atomic configurations inherent to the random alloy prevents the accurate application of standard force-based atomistic/continuum (a/c) coupling. Errors arise because the two transitions, from atomistic to continuum and from random-to-homogeneous, occur at the same location. Here, two methods for a/c coupling that mitigate errors arising in the standard method are proposed, studied, and validated. In one method, the desired atomistic domain and its nearby surroundings are fully relaxed to an equilibrium structure and then inserted into the coupled problem as the reference configuration. This reduces the effects of the random-to-homogeneous transition, and guarantees no spurious stress at zero load. In the second method, the random-to-homogeneous transition is spatially separated from the atomistic-continuum transition by introducing a small buffer zone of well-defined ‘average atoms’. The random-to-homogeneous transition is then accomplished fully atomistically while the atomistic to continuum transition is accomplished in a homogeneous material. The two methods are validated through comparisons of the stresses in the coupled method versus the true atomistic system for three different solid solution alloys (Al-5%Mg, Ni-15%Al, and medium entropy FeNiCr) as described by EAM interatomic potentials. Spurious stresses for both methods and across all three materials are negligible (≈5 MPa) relative to stresses arising in realistic mechanical problems of interest. These new methods thus enable the accurate study of mechanics boundary value problems in random alloys for problems where it is essential to capture atomistic phenomena in some localized region of the random alloy. read less USED (high confidence) N. T. Trung, H. Phuong, and M. Starostenkov, “Molecular dynamics simulation of displacement cascades in B2 NiAl,” Letters on Materials. 2019. link Times cited: 5 Abstract: This study is focused on the behavior of B2 NiAl alloy under… read moreAbstract: This study is focused on the behavior of B2 NiAl alloy under irradiation. For achieving this aim, we performed a series of molecular dynamics simulations of displacement cascades with the primary knock-on atom (PKA) energy from 1 keV to 40 keV. To ensure that the boundary effects were not important, the simulation boxes contained from 60 × 60 × 60 to 112 ×112 ×112 unit cells with 432 000 to 2 809 856 atoms, depending on the PKA energy. To correctly reproduce atomic interactions at short distances, the Mishin EAM potentials were stiffened in a short range using polynomial regression to join the equilibrium part of the EAM potential to a short range of ZBL potential and intermediate interatomic distance with the corresponding pairwise energy based on the density function theory calculation. To obtain statistically meaningful results, 10 simulations were performed for each PKA energy. Each cascade simulation lasted approximately from 12 ps to 42 ps, depending on the PKA energy; in these time intervals the number of Frenkel pairs (FP) became stable. We discuss in detail the time evolution of Frenkel pairs, the avalanche effect in the sonic phase and the origin of the permanent defect. The results from our simulations, including the number of stable Frenkel pairs, chemical composition, clustering of the defect production are in good agreement with the reports from the literature. read less USED (high confidence) Y. Xiong et al., “Effect of particle packing and density on shock response in ordered arrays of Ni + Al nanoparticles.,” Physical chemistry chemical physics : PCCP. 2019. link Times cited: 6 Abstract: We investigate the shock response of Ni + Al reactive nanopa… read moreAbstract: We investigate the shock response of Ni + Al reactive nanoparticle systems through molecular dynamics simulations. The powder configurations with varying arrangements and densities are constructed by stacking equal-sized Ni and Al particles based on five typical crystal structures, i.e., zinc-blende, NaCl, CsCl, AuCu and the close-packed. The effects of configuration and shock strength on mechanochemical and diffusion processes in the shock-induced chemical reactions are characterized. A reaction kinetic model is developed to describe these behaviors, assess the extent of mechanochemical effect, and explain the occurrence of ultra-fast reaction. Significant dependence of shock wave velocity, plastic deformation, temperature response, chemistry and microstructure change on particle packing and density is observed under shock loading at the same piston velocity, but we see a relatively weak dependency on the stacking mode with the same density. Our results indicate the important role of particle coordination number and density in shock response of energetic powder materials. read less USED (high confidence) B. Witbeck and D. Spearot, “Grain size effects on Ni/Al nanolaminate combustion,” Journal of Materials Research. 2019. link Times cited: 7 Abstract: Reactions in Ni/Al nanolaminates exhibit high combustion tem… read moreAbstract: Reactions in Ni/Al nanolaminates exhibit high combustion temperatures and wave speeds that are customizable through changes to nanostructure. Nanolaminates fabricated via vapor deposition exhibit columnar grains with average diameters on the order of the individual layer thickness; yet, their role on nanolaminate combustion has not been previously investigated. The current work uses molecular dynamics simulations to elucidate the effect of grain size on reaction rates and combustion temperatures in Ni/Al nanolaminates. Decreasing grain size is shown to increase reaction rates as well as increase peak temperatures consistent with the excess enthalpy of smaller grain sizes. Additionally, grain boundaries provide heterogenous nucleation sites for the diffusion-restricting B2–NiAl phase. Focusing on Ni diffusion into liquid Al, an effective diffusion coefficient is computed as a function of grain size, which may be used in thermodynamic models for this stage of the reaction. read less USED (high confidence) P. Yi, M. Falk, and T. Weihs, “Intermetallic formation at deeply supercooled Ni/Al multilayer interfaces: A molecular dynamics study,” Journal of Applied Physics. 2018. link Times cited: 7 Abstract: NiAl intermetallic formation occurs along the interfaces in … read moreAbstract: NiAl intermetallic formation occurs along the interfaces in the Ni/Al multilayer system during molecular dynamics simulations of deep (>50%) supercooling. The simulations begin with a crystalline solid solution at the Ni/Al interfaces that melts at 800 K, a supercooling of 56% of NiAl's simulated melting temperature (1800 K), and undergoes solid-state amorphization at 650 K, a supercooling of 64%. The intermetallic phase, NiAl, then forms at the interface from the melted/amorphous region through heterogeneous nucleation followed by growth in both lateral and normal directions. Upon nucleation, the intermetallic phase retains a fraction of the composition gradient present within the initial solid solution, and that fraction is always larger at 650 K, compared to 800 K, for the same initial composition gradient. Kinetics of the transformation follows the Johnson-Mehl-Avrami model, and an Avrami exponent of 0.5 was extracted at 800 K and 0.1 at 650 K. The NiAl formation is growth-controlled and the growth rate is found to increase with the decreasing initial composition gradient. Our finding supports a growth-competition mechanism of phase selection for interfacial reactions.NiAl intermetallic formation occurs along the interfaces in the Ni/Al multilayer system during molecular dynamics simulations of deep (>50%) supercooling. The simulations begin with a crystalline solid solution at the Ni/Al interfaces that melts at 800 K, a supercooling of 56% of NiAl's simulated melting temperature (1800 K), and undergoes solid-state amorphization at 650 K, a supercooling of 64%. The intermetallic phase, NiAl, then forms at the interface from the melted/amorphous region through heterogeneous nucleation followed by growth in both lateral and normal directions. Upon nucleation, the intermetallic phase retains a fraction of the composition gradient present within the initial solid solution, and that fraction is always larger at 650 K, compared to 800 K, for the same initial composition gradient. Kinetics of the transformation follows the Johnson-Mehl-Avrami model, and an Avrami exponent of 0.5 was extracted at 800 K and 0.1 at 650 K. The NiAl formation is growth-controlled and the growth ra... read less USED (high confidence) W. Nöhring and W. Curtin, “Cross-slip of long dislocations in FCC solid solutions,” Acta Materialia. 2018. link Times cited: 37 USED (high confidence) Y. Rong, P. Ji, M. He, Y. Zhang, and Y. Tang, “Atomistic insights into the exothermic self-sustained alloying of Al-shell/Ni-core nanoparticle triggered by laser irradiation.,” Physical chemistry chemical physics : PCCP. 2018. link Times cited: 3 Abstract: By imposing a picosecond laser pulse irradiation on an Al-sh… read moreAbstract: By imposing a picosecond laser pulse irradiation on an Al-shell/Ni-core nanoparticle, an exothermic self-sustained alloying is triggered. Molecular dynamics simulation is implemented to get atomistic insights into the alloying process. The nanoparticle is composed by an equiatomic number of Al atoms in the shell and Ni atoms in the core. Due to the absorption of laser energy from the surface of the nanoparticle, atomic motion becomes active. The inter-diffusion of Ni and Al atoms results in thermal energy generation. It is found that the incident laser energy is responsible for controlling the degree of self-heating of the nanoparticle by governing the potential energy change during the inter-diffusion of Al-shell and Ni-core atoms. read less USED (high confidence) B. Witbeck, J. Sink, and D. Spearot, “Influence of vacancy defect concentration on the combustion of reactive Ni/Al nanolaminates,” Journal of Applied Physics. 2018. link Times cited: 13 Abstract: Self-propagating reactions in Ni/Al nanolaminates have been … read moreAbstract: Self-propagating reactions in Ni/Al nanolaminates have been widely studied for their high combustion temperatures surpassing 1900 K and rapid combustion wave speeds exceeding 10 m/s. These combustion characteristics have motivated unique industrial applications, such as soldering of electrical components, and possible military applications. Unfortunately, there is a limited understanding of the effect of lattice defects on combustion characteristics. This work explores the effect of vacancy concentration on the combustion rate and peak temperature of reactive Ni/Al nanolaminates. Increasing vacancy concentration increases both reaction rates and peak reaction temperatures. For the reaction rate, vacancy concentration effects are shown to be interdependent with bilayer thickness, initial temperature, and hydrostatic pressure. The effects on reaction peak temperature are independent of these other system parameters. A new method for mapping vacancy and composition profiles is presented to demonstrate the formation and migration of vacancies during the self-propagating reaction.Self-propagating reactions in Ni/Al nanolaminates have been widely studied for their high combustion temperatures surpassing 1900 K and rapid combustion wave speeds exceeding 10 m/s. These combustion characteristics have motivated unique industrial applications, such as soldering of electrical components, and possible military applications. Unfortunately, there is a limited understanding of the effect of lattice defects on combustion characteristics. This work explores the effect of vacancy concentration on the combustion rate and peak temperature of reactive Ni/Al nanolaminates. Increasing vacancy concentration increases both reaction rates and peak reaction temperatures. For the reaction rate, vacancy concentration effects are shown to be interdependent with bilayer thickness, initial temperature, and hydrostatic pressure. The effects on reaction peak temperature are independent of these other system parameters. A new method for mapping vacancy and composition profiles is presented to demonstrate the fo... read less USED (high confidence) Q.-ul-ain Sahi and Y.-S. Kim, “Atomistic simulations to characterize the influence of applied strain and PKA energy on radiation damage evolution in pure aluminum,” The European Physical Journal B. 2018. link Times cited: 2 USED (high confidence) L. Yang, “Structures and dynamics investigation of phase selection in metallic alloy systems.” 2018. link Times cited: 1 Abstract: Different phases of metallic alloys have a wide range of app… read moreAbstract: Different phases of metallic alloys have a wide range of applications. However, the driving mechanisms of the phase selections can be complex. For example, the detailed pathways of the phase transitions in the devitrification process still lack a comprehensive interpretation. So, the understanding of the driving mechanisms of the phase selections is very important. In this thesis, we focus on the study of the Al-Sm and other related metallic alloy systems by simulation and experiment. A procedure to evaluate the free energy has been developed within the framework of thermodynamic integration, coupled with extensive GPUaccelerated molecular dynamics (MD) simulations; The “spatially-correlated site occupancy” has been observed and measured in the -Al60Sm11 phase. Contrary to the common belief that nonstoichiometry is often the outcome of the interplay of enthalpy of formation and configurational entropy at finite temperatures, our results from Monte Carlo (MC) and molecular dynamics (MD) simulations, imply that kinetic effects, especially the limited diffusivity of Sm is crucial for the appearance of the observed spatial correlations in the nonstoichiometric phase. Moreover, in order to overcome the time limitation in MD simulation of the nucleation process, a “persistent-embryo method” has been developed, which opens a new avenue to study solidification under realistic experimental conditions via atomistic computer simulation. Based on this thesis study, we have achieved deeper understanding of the driving mechanisms of the phase selections, and laid a foundation for further prediction and control of the fabrication of novel metallic alloy materials. This thesis consists of the following seven chapters: read less USED (high confidence) L. Yang, F. Zhang, C. Wang, K. Ho, and A. Travesset, “Implementation of metal-friendly EAM/FS-type semi-empirical potentials in HOOMD-blue: A GPU-accelerated molecular dynamics software,” J. Comput. Phys. 2018. link Times cited: 8 USED (high confidence) D. Choudhuri, R. Banerjee, and S. G. Srinivasan, “Uniaxial deformation of face-centered-cubic(Ni)-ordered B2(NiAl) bicrystals: atomistic mechanisms near a Kurdjumov–Sachs interface,” Journal of Materials Science. 2018. link Times cited: 8 USED (high confidence) H. Pang, Q. Bi, H. S. Huang, and Y. Lü, “Anisotropic stress inhibits crystallization in Cu-Zr glass-forming liquids.,” The Journal of chemical physics. 2017. link Times cited: 3 Abstract: Liquids attain a metastable state without crystallizing by c… read moreAbstract: Liquids attain a metastable state without crystallizing by cooling rapidly to a given temperature below the melting point. With increasing supercooling, the nucleation rate would show an increase based on the prediction of the classical nucleation theory. It is generally thought that the nucleation rate will reach the maximum upon approaching the glass transition temperature, Tg, for glass-forming liquids. We report that there exists a supercooled region above Tg in which the crystallization has actually been severely suppressed. Our molecular dynamics simulations show that the growth of embryos in the supercooled Cu60Zr40 melt is subjected to a strong anisotropic stress associated with the dynamic heterogeneity. Its long-range effect drives the embryo to grow into a ramified morphology so that the interface energy dominates over the embryo growth, leading to the suppression of nucleation. read less USED (high confidence) A. Mayer and A. A. Ebel, “Shock-induced compaction of nanoparticle layers into nanostructured coating,” Journal of Applied Physics. 2017. link Times cited: 16 Abstract: A new process of shock wave consolidation of nanoparticles i… read moreAbstract: A new process of shock wave consolidation of nanoparticles into a nanocrystalline coating is theoretically considered. In the proposed scheme, the nanoparticle layers, which are attached to the substrate surface by adhesion, are compacted by plane ultra-short shock waves coming from the substrate. The initial adhesion is self-arisen at any contact between the nanoparticles without a pre-compression. The absence of the nanoparticle ejections due to the shock wave action is connected with the strong adhesive forces, which allow nanoparticles to be attached to each other and to substrate while they are being compacted; this should be valid for small enough nanoparticles. Severe plastic deformation of the nanoparticles and the increased temperature due to collapse of voids between them facilitate their compaction into the monolithic nanocrystalline layer. We consider the examples of Cu and Ni nanoparticles on Al substrate using molecular dynamic simulations. We show the efficiency of the action of multiple sh... read less USED (high confidence) V. Turlo, F. Baras, and O. Politano, “Comparative study of embedded-atom methods applied to the reactivity in the Ni–Al system,” Modelling and Simulation in Materials Science and Engineering. 2017. link Times cited: 23 Abstract: Structural, thermodynamic, atomic and thermal transport prop… read moreAbstract: Structural, thermodynamic, atomic and thermal transport properties of solid and liquid phases of the Ni–Al system were studied by means of MD simulations using three embedded-atom method (EAM) potentials developed by Mishin and colleagues (Mishin et al 2002 Phys. Rev. B 65 224114; Mishin 2004 Acta Mater. 52 145167; Purja Pun and Mishin 2009 Phil. Mag. 89 32453267). The extracted properties (lattice parameter, enthalpy, heat capacity, mass diffusivity and thermal conductivity) were compared with experimental data. The limitations of EAM potentials for studying different aspects of reactivity were assessed for each potential separately. read less USED (high confidence) Y. Gao and Z. Jin, “Interaction between lattice dislocations and low-angle grain boundaries in Ni via molecular dynamics simulations,” Molecular Simulation. 2017. link Times cited: 15 Abstract: Low-angle grain boundaries (LAGBs) may show up frequently as… read moreAbstract: Low-angle grain boundaries (LAGBs) may show up frequently as distinct dislocation products such as in the processes of work hardening, recovery and recrystallisation of metals and alloys. To reveal their mechanical behaviours, interactions between lattice dislocation and symmetric tilt and twist LAGBs are studied with molecular dynamics simulations. It is shown that dislocation reaction and slip transmission depend on the structure of LAGB, the character of incident dislocation and the particular glide planes inhabiting the incoming slip. For tilt LAGBs, a free slip-transmission process is identified where dislocations can be forced to penetrate through the boundary without inducing dislocation reaction. Otherwise, the incident slip tends to be trapped or absorbed by those intrinsic grain boundary dislocations. With increasing the applied strain, a number of dislocation reactions can be triggered, which may lead to indirect slip transmission across the boundary. read less USED (high confidence) Y. Xiong, S. Xiao, H. Deng, W. Zhu, and W. Hu, “Investigation of the shock-induced chemical reaction (SICR) in Ni + Al nanoparticle mixtures.,” Physical chemistry chemical physics : PCCP. 2017. link Times cited: 14 Abstract: Molecular dynamics (MD) simulations are used to investigate … read moreAbstract: Molecular dynamics (MD) simulations are used to investigate the shock-compression response of Ni + Al spherical nanoparticles arranged in a NaCl-like structure. The deformation and reaction characteristics are studied from the particle level to the atomic scale at various piston velocities. Shock-induced chemical reactions (SICRs) occur during non-equilibrium processes, accompanied by a sharp rise in temperature and rapid mixing of atoms. The preferentially deformed Al particles form a high-speed mass flow relative to the Ni at the shock front, which impinges on the Ni particles, and mixing of Ni and Al atoms occurs immediately at the interface. The particle velocity dispersion (PVD) that appears at the shock front has important implications for the initiation of shock-induced chemical reactions. We show that dislocations are mainly generated at the beginning of particle deformation or at the shock front, and do not directly affect the occurrence of SICRs. The intimate contact of the molten Al and the amorphous Ni is found to be critical to the subsequent reactions for the extensive mixing of Ni and Al. We conclude that the mechanisms of SICRs involve mechanochemical processes near the shock front and subsequent interdiffusion processes. read less USED (high confidence) C. Li, Y. Luan, X. J. Han, and J. G. Li, “Role of chemical short-range order in atomic dynamics decoupling,” Molecular Simulation. 2017. link Times cited: 2 Abstract: Using molecular dynamics simulation, α-relaxation times τα a… read moreAbstract: Using molecular dynamics simulation, α-relaxation times τα and self-diffusion coefficients D for Al90Fe10, Al80Fe20, Al70Fe30, Al60Fe40 and Al80Ni20 (as a contrast system) melts have been systematically computed over a wide temperature range (1000–2000 K). The computed results reveal that τFe/τAl (or DAl/DFe) for the Al90Fe10 and Al80Fe20 melts exhibit an accelerating increase with cooling at temperatures lower than 1400 K, implying a clear decoupling of dynamics of Al and Fe (here referred to as component decoupling). This component decoupling diminishes in Al70Fe30 melt and disappears in Al60Fe40 melt. We simultaneously checked the relaxation decoupling (i.e. the decoupling between α-relaxation and diffusion). The relaxation decoupling is clear in Al60Fe40 melt, less clear in Al70Fe30 melt and not shown in Al80Fe20 and Al90Fe10 melt. It exhibits a tendency counter to that of component decoupling with changing composition, arguing that relaxation decoupling does not necessarily lead to component decoupling. This finding is contradicted against the conventional view that component decoupling is believed as a result of relaxation decoupling. We further attributed such a contradiction to the difference in the degree of chemical short-range order (CSRO) in melts. The existence of CSRO can increase the cooperativity in dynamics of different components. So it is better to consider component decoupling as a combined effect of relaxation decoupling and CSRO. This work would be helpful in improving our understanding of the relationship between the two kinds of decoupling. read less USED (high confidence) M. Falk and T. Weihs, “Suppression of homogeneous crystal nucleation of the NiAl intermetallic by a composition gradient: A molecular dynamics study,” Journal of Chemical Physics. 2017. link Times cited: 10 Abstract: Molecular dynamics simulations of homogeneous nucleation of … read moreAbstract: Molecular dynamics simulations of homogeneous nucleation of the NiAl intermetallic phase from a liquid solution on cooling indicate that this phase transformation is suppressed in the presence of a composition gradient. A simulation method is designed to generate a sustaining composition gradient at the interface between two materials. As the composition gradient increases, the nucleation energy barrier rises, the critical nucleus size increases, and the nucleus shape develops an increasing asymmetry. A polymorphic nucleation model for a disk-shaped nucleus that incorporates the composition dependence of interfacial free energies was observed to describe the atomic-scale details of the simulation well. Critical nuclei shapes and volumes predicted by the model match with those appearing in the molecular dynamics simulations. read less USED (high confidence) M. Fu, Q. Bi, and Y. Lü, “Kinetics of Spherical Interface in Crystal Growth,” Chinese Physics Letters. 2017. link Times cited: 1 USED (high confidence) V. Turlo, O. Politano, and F. Baras, “Alloying propagation in nanometric Ni/Al multilayers: A molecular dynamics study,” Journal of Applied Physics. 2017. link Times cited: 26 Abstract: In nanometric metallic multilayers such as Ni/Al, the alloyi… read moreAbstract: In nanometric metallic multilayers such as Ni/Al, the alloying reaction proceeds in the form of a propagating wave. We studied the different phase transformations involved in the reactive wave propagation by means of molecular dynamics. The focus was on a specific regime that involves melting of reactants, intermixing of reactants, and formation of an intermetallic compound. We found that the wave consists of two stages. The first front is associated with a dissolution process and propagates at several meters per second, while the second front is due to the crystallization of the final product and is slower, leading to a specific microstructure with alternated large grains of NiAl and liquid regions in the front propagation direction. Three main exothermic processes were identified, including grain coarsening. Their respective contributions were evaluated. We developed a new texture analysis tool that allowed us to follow the evolution of the microstructure and the dynamics of the grain orientation. read less USED (high confidence) J. Huang et al., “Molecular dynamics simulation of persistent slip bands formation in nickel-base superalloys,” International Journal of Automation and Computing. 2017. link Times cited: 2 USED (high confidence) J. Huang et al., “Molecular dynamics simulation of persistent slip bands formation in nickel-base superalloys,” International Journal of Automation and Computing. 2016. link Times cited: 0 USED (high confidence) W. Tucker and P. Schelling, “Thermodiffusion in liquid binary alloys computed from molecular-dynamics simulation and the Green-Kubo formalism,” Computational Materials Science. 2016. link Times cited: 8 USED (high confidence) S. L. Thomas, A. King, and D. Srolovitz, “When twins collide: Twin junctions in nanocrystalline nickel,” Acta Materialia. 2016. link Times cited: 41 USED (high confidence) L. Ma, S. Xiao, H. Deng, and W. Hu, “Tensile mechanical properties of Ni‐based superalloy of nanophases using molecular dynamics simulation,” physica status solidi (b). 2016. link Times cited: 19 Abstract: The mechanical properties of Ni/Ni3Al monocrystal of nanopha… read moreAbstract: The mechanical properties of Ni/Ni3Al monocrystal of nanophases with varying temperatures, strain rates, and phase sizes have been studied using molecular dynamics simulation. The simulation results show that the primary deformation mechanisms in Ni/Ni3Al monocrystal of nanophases were slip bands and antiphase boundaries at room temperature. The studies on the effects of temperature showed that the yield strain, yield strength, and elastic module decreased as temperature increased. However, the influences of strain rate and phase size on the mechanical properties of Ni/Ni3Al monocrystal of nanophases showed that the high strain rate led to the increase of yield stress, and the phase sizes had no significant influence on the maximum yield stress. In addition, the behavior of crack propagation in the model of Ni/Ni3Al interface was investigated under cyclic loading, and it was found that the interface of Ni/Ni3Al was resistance to the fatigue crack propagation. read less USED (high confidence) K. Manukyan et al., “Exothermic Self-Sustained Waves with Amorphous Nickel,” Journal of Physical Chemistry C. 2016. link Times cited: 22 Abstract: The synthesis of amorphous Ni (a-Ni) using a liquid-phase ch… read moreAbstract: The synthesis of amorphous Ni (a-Ni) using a liquid-phase chemical reduction approach is reported. Detailed structural analysis indicates that this method allows for efficient fabrication of high surface area (210 m2/g) amorphous Ni nanopowder with low impurity content. We investigated the self-propagating exothermic waves associated with crystallization of Ni from the amorphous precursor. Time-resolved X-ray diffraction indicates that amorphous nickel crystallizes in the temperature range 445–480 K. High-speed infrared imaging reveals that local preheating of compressed a-Ni nanopowder triggers a self-sustaining crystallization wave that propagates with velocity ∼0.3 mm/s. The maximum temperature of crystallization wave depends on the sample density and can be as high as 600 K. The Kissinger approach is used to determine the apparent activation energy (55.4 ± 4 kJ/mol) of crystallization. The self-diffusion activation energy of Ni atoms in a-Ni is ∼60 kJ/mol, determined through molecular dynamics (MD) si... read less USED (high confidence) G. P. P. Pun, K. Darling, L. Kecskes, and Y. Mishin, “Angular-dependent interatomic potential for the Cu–Ta system and its application to structural stability of nano-crystalline alloys,” Acta Materialia. 2015. link Times cited: 92 USED (high confidence) X. Yan and Y. Lü, “Mechanism of abnormally slow crystal growth of CuZr alloy.,” The Journal of chemical physics. 2015. link Times cited: 14 Abstract: Crystal growth of the glass-forming CuZr alloy is shown to b… read moreAbstract: Crystal growth of the glass-forming CuZr alloy is shown to be abnormally slow, which suggests a new method to identify the good glass-forming alloys. The crystal growth of elemental Cu, Pd and binary NiAl, CuZr alloys is systematically studied with the aid of molecular dynamics simulations. The temperature dependence of the growth velocity indicates the different growth mechanisms between the elemental and the alloy systems. The high-speed growth featuring the elemental metals is dominated by the non-activated collision between liquid-like atoms and interface, and the low-speed growth for NiAl and CuZr is determined by the diffusion across the interface. We find that, in contrast to Cu, Pd, and NiAl, a strong stress layering arisen from the density and the local order layering forms in front of the liquid-crystal interface of CuZr alloy, which causes a slow diffusion zone. The formation of the slow diffusion zone suppresses the interface moving, resulting in much small growth velocity of CuZr alloy. We provide a direct evidence of this explanation by applying the compressive stress normal to the interface. The compression is shown to boost the stress layering in CuZr significantly, correspondingly enhancing the slow diffusion zone, and eventually slowing down the crystal growth of CuZr alloy immediately. In contrast, the growth of Cu, Pd, and NiAl is increased by the compression because the low diffusion zones in them are never well developed. read less USED (high confidence) K. Shreiber and D. Mordehai, “Dislocation-nucleation-controlled deformation of Ni3Al nanocubes in molecular dynamics simulations,” Modelling and Simulation in Materials Science and Engineering. 2015. link Times cited: 20 Abstract: The strength of Ni3Al nanocubes under compression, as well a… read moreAbstract: The strength of Ni3Al nanocubes under compression, as well as the underlying dislocation mechanisms, are analysed in molecular dynamics simulations. For this purpose, the bond-order parameters analysis is extended to multi-atomic systems in order to identify the intrinsic planar defects in Ni3Al. We benchmarked different interatomic potentials and compared the results with experimental ones. The different potentials resulted in different elastic responses under compression but all yielded abruptly at a compressive stress of about 7–8 GPa, followed by a large strain burst. The nanocubes yielded by nucleating Shockley partial dislocations at the vertices on {1 1 1} ?> planes, leaving a structure of faulted planes. The mechanical response was found to be size independent, which we attribute to the cubical shape of the nanoparticle and the lack of stress gradients at its vertices. read less USED (high confidence) T. Lee, A. Caro, and M. Demkowicz, “Atomistic modeling of radiation-induced disordering and dissolution at a Ni/Ni_3Al interface,” Journal of Materials Research. 2015. link Times cited: 15 Abstract: L1_2-ordered γ′ precipitates embedded in a fcc γ matrix impa… read moreAbstract: L1_2-ordered γ′ precipitates embedded in a fcc γ matrix impart excellent mechanical properties to nickel-base superalloys. However, these enhanced mechanical properties are lost under irradiation, which causes the γ′ precipitates to disorder and dissolve. We conduct an atomic-level study of radiation-induced disordering and dissolution at a coherent (100) facet of an initially ordered γ′ Ni_3Al precipitate neighboring a pure Ni γ matrix. Using molecular dynamics, we simulate collision-induced events by sequentially introducing 10 keV primary knock-on atoms with random positions and directions. In the absence of thermally assisted recovery processes, the ordered Ni_3Al layer disorders rapidly within 0.1–0.2 dpa and then gradually dissolves into the adjacent Ni layer at higher doses. Both the disordering efficiency and mixing parameter calculated from the simulations lie within the range of values found by experiments carried out at room temperature, where thermally activated diffusion is insignificant. read less USED (high confidence) W. Song and S.-jin Zhao, “Effects of partitioned enthalpy of mixing on glass-forming ability.,” The Journal of chemical physics. 2015. link Times cited: 4 Abstract: We explore the inherent reason at atomic level for the glass… read moreAbstract: We explore the inherent reason at atomic level for the glass-forming ability of alloys by molecular simulation, in which the effect of partitioned enthalpy of mixing is studied. Based on Morse potential, we divide the enthalpy of mixing into three parts: the chemical part (ΔEnn), strain part (ΔEstrain), and non-bond part (ΔEnnn). We find that a large negative ΔEnn value represents strong AB chemical bonding in AB alloy and is the driving force to form a local ordered structure, meanwhile the transformed local ordered structure needs to satisfy the condition (ΔEnn/2 + ΔEstrain) < 0 to be stabilized. Understanding the chemical and strain parts of enthalpy of mixing is helpful to design a new metallic glass with a good glass forming ability. Moreover, two types of metallic glasses (i.e., "strain dominant" and "chemical dominant") are classified according to the relative importance between chemical effect and strain effect, which enriches our knowledge of the forming mechanism of metallic glass. Finally, a soft sphere model is established, different from the common hard sphere model. read less USED (high confidence) L. Ma, S. Xiao, H. Deng, and W. Hu, “Atomic simulation of fatigue crack propagation in Ni3Al,” Applied Physics A. 2015. link Times cited: 13 USED (high confidence) L. Ma, S. Xiao, H. Deng, and W. Hu, “Atomic simulation of fatigue crack propagation in Ni3Al,” Applied Physics A. 2014. link Times cited: 0 USED (high confidence) H. Sun and C. Deng, “Direct quantification of solute effects on grain boundary motion by atomistic simulations,” Computational Materials Science. 2014. link Times cited: 35 USED (high confidence) K. A. Bukreeva, R. Babicheva, A. B. Sultanguzhina, S. Dmitriev, K. Zhou, and R. Mulyukov, “Effect of temperature on inhomogeneous elastic deformation and negative stiffness of NiAl and FeAl alloy nanofilms,” Physics of the Solid State. 2014. link Times cited: 5 USED (high confidence) W.-jin Zhang, Y. Peng, and Z.-L. Liu, “Molecular dynamics simulations of the melting curve of NiAl alloy under pressure,” AIP Advances. 2014. link Times cited: 22 Abstract: The melting curve of B2-NiAl alloy under pressure has been i… read moreAbstract: The melting curve of B2-NiAl alloy under pressure has been investigated using molecular dynamics technique and the embedded atom method (EAM) potential. The melting temperatures were determined with two approaches, the one-phase and the two-phase methods. The first one simulates a homogeneous melting, while the second one involves a heterogeneous melting of materials. Both approaches reduce the superheating effectively and their results are close to each other at the applied pressures. By fitting the well-known Simon equation to our melting data, we yielded the melting curves for NiAl: 1783(1 + P/9.801)0.298 (one-phase approach), 1850(1 + P/12.806)0.357 (two-phase approach). The good agreement of the resulting equation of states and the zero-pressure melting point (calc., 1850 ± 25 K, exp., 1911 K) with experiment proved the correctness of these results. These melting data complemented the absence of experimental high-pressure melting of NiAl. To check the transferability of this EAM potential, we have also predicted the melting curves of pure nickel and pure aluminum. Results show the calculated melting point of Nickel agrees well with experiment at zero pressure, while the melting point of aluminum is slightly higher than experiment. read less USED (high confidence) C. Becker et al., “Thermodynamic modelling of liquids: CALPHAD approaches and contributions from statistical physics,” physica status solidi (b). 2014. link Times cited: 32 Abstract: We describe current approaches to thermodynamic modelling of… read moreAbstract: We describe current approaches to thermodynamic modelling of liquids for the CALPHAD method, the use of available experimental methods and results in this type of modelling, and considerations in the use of atomic‐scale simulation methods to inform a CALPHAD approach. We begin with an overview of the formalism currently used in CALPHAD to describe the temperature dependence of the liquid Gibbs free energy and outline opportunities for improvement by reviewing the current physical understanding of the liquid. Brief descriptions of experimental methods for extracting high‐temperature data on liquids and the preparation of undercooled liquid samples are presented. Properties of a well‐determined substance, B2 O3, including the glass transition, are then discussed in detail to emphasize specific modelling requirements for the liquid. We then examine the two‐state model proposed for CALPHAD in detail and compare results with experiment and theory, where available. We further examine the contributions of atomic‐scale methods to the understanding of liquids and their potential for supplementing available data. We discuss molecular dynamics (MD) and Monte Carlo methods that employ atomic interactions from classical interatomic potentials, as well as contributions from ab initio MD. We conclude with a summary of our findings. read less USED (high confidence) K. A. Bukreeva, R. Babicheva, S. Dmitriev, K. Zhou, and R. Mulyukov, “Inhomogeneous elastic deformation of nanofilms and nanowires of NiAl and FeAl alloys,” JETP Letters. 2013. link Times cited: 13 USED (high confidence) L. Sandoval, G. Campbell, and J. Marian, “Thermodynamic interpretation of reactive processes in Ni–Al nanolayers from atomistic simulations,” Modelling and Simulation in Materials Science and Engineering. 2013. link Times cited: 13 Abstract: Metals that can form intermetallic compounds by exothermic r… read moreAbstract: Metals that can form intermetallic compounds by exothermic reactions constitute a class of reactive materials with multiple applications. Ni–Al laminates of thin alternating layers are being considered as model nanometric metallic multilayers for studying various reaction processes. However, the reaction kinetics at short timescales after mixing are not entirely understood. In this work, we calculate the free energies of Ni–Al alloys as a function of composition and temperature for different solid phases using thermodynamic integration based on state-of-the-art interatomic potentials. We use this information to interpret molecular dynamics (MD) simulations of bilayer systems at 800 K and zero pressure, both in isothermal and isenthalpic conditions. We find that a disordered phase always forms upon mixing as a precursor to a more stable nano crystalline B2 phase. We construe the reactions observed in terms of thermodynamic trajectories governed by the state variables computed. Simulated times of up to 30 ns were achieved, which provides a window to phenomena not previously observed in MD simulations. Our results provide insight into the early experimental reaction timescales and suggest that the path (segregated reactants) → (disordered phase) → (B2 structure) is always realized irrespective of the imposed boundary conditions. read less USED (high confidence) R. Babicheva, K. A. Bukreeva, S. Dmitriev, R. Mulyukov, and K. Zhou, “Negative Stiffness Demonstrated by NiAl Nanofilms,” computational methods in science and technology. 2013. link Times cited: 2 Abstract: This paper studies the uniaxial strain control tension of Ni… read moreAbstract: This paper studies the uniaxial strain control tension of NiAl nanofilms via molecular dynamics simulations. The nanofilm deforms elastically until fracture at tensile strain is as large as 37%. The stress-strain curve has a range where tensile deformation develops at decreasing tensile stress, thus indicating negative stiffness. Such deformation is thermodynamically unstable and the nanofilm splits into domains with two different values of elastic strain. Deformation within the unstable range is controlled by motion of the domain walls, resulting in the domains with larger strain grow at the expense of the domains with smaller strain. read less USED (high confidence) K. Manukyan et al., “Tailored Reactivity of Ni+Al Nanocomposites: Microstructural Correlations,” Journal of Physical Chemistry C. 2012. link Times cited: 97 Abstract: An efficient approach that combines short-term (minutes) hig… read moreAbstract: An efficient approach that combines short-term (minutes) high-energy dry ball milling and wet grinding to tailor the nano- and microstructure of Ni+Al composite reactive particles is reported. Varying the ball-milling conditions allows control of the volume fraction of two distinct milling-induced microstructures, that is, coarse and nanolaminated. It is found that increasing the fraction of nanolaminated structure present in the composite particles leads to a decrease in their ignition temperature (Tig) from 700 and 500 K. Material with nanolaminated microstructure is also found to be more sensitive to impact ignition when compared with particles with a coarse microstructure. It is shown that kinetic energy (Wcr) thresholds for impact ignition, obtained for an optimized nanolaminated microstructure, is only 100 J. High-speed imaging showed that the impact-induced ignition occurs through formation of hot spots caused by impact. Molecular dynamic simulations of a model system suggest that impact-induced lo... read less USED (high confidence) M. Cherukara, K. Vishnu, and A. Strachan, “Role of nanostructure on reaction and transport in Ni/Al intermolecular reactive composites,” Physical Review B. 2012. link Times cited: 35 USED (high confidence) N. S. Weingarten and B. Rice, “A molecular dynamics study of the role of relative melting temperatures in reactive Ni/Al nanolaminates,” Journal of Physics: Condensed Matter. 2011. link Times cited: 38 Abstract: Molecular dynamics (MD) simulations using a recently develop… read moreAbstract: Molecular dynamics (MD) simulations using a recently developed first-principles-based embedded-atom-method (EAM) potential are used to simulate the exothermic alloying reactions of a Ni/Al bilayer initially equilibrated at 1200 K. Simulations are performed in the isobaric–isoenthalpic (NPH) ensemble, which provides insight into the influence of pressure on atomic mixing and the subsequent alloying reaction. For pressures lower than 8 GPa, the mechanism of mixing is the same: as mixing and reaction occur at the interface, the heat generated first melts the Al layer, and subsequent mixing leads to further heat generation after which the Ni layer melts, leading to additional mixing until the alloying reactions are completed. However, for simulations at pressures higher than 8 GPa, the reaction does not occur within the time interval of the simulation. The results will be compared with our previous simulations of a Ni/Al bilayer using a different interatomic potential, which predicts substantially different pressure-dependent melting behavior of the pure components. This comparative study suggests that pressure-dependent melting behavior of components of reactive materials can be used to influence reaction rates and mechanisms. read less USED (high confidence) J. Rojek, S. Nosewicz, M. Maździarz, P. Kowalczyk, K. Wawrzyk, and D. Lumelskyj, “Modeling of a Sintering Process at Various Scales,” Procedia Engineering. 2017. link Times cited: 40 USED (high confidence) A. Khoei, A. R. Sameti, H. Mofatteh, and M. Babaei, “Compaction simulation of nano-crystalline metals with molecular dynamics analysis.” 2016. link Times cited: 0 Abstract: The molecular-dynamics analysis is presented for 3D compacti… read moreAbstract: The molecular-dynamics analysis is presented for 3D compaction simulation of nano-crystalline metals under uniaxial compaction process. The nano-crystalline metals consist of nickel and aluminum nano-particles, which are mixed with specified proportions. The EAM pair-potential is employed to model the formation of nano-particles at different temperatures, number of nano-particles, and mixing ratio of Ni and Al nano-particles to form the component into the shape of a die. The die-walls are modeled using the Lennard-Jones inter-atomic potential between the atoms of nano-particles and die-walls. The forming process is model in uniaxial compression, which is simulated until the full-dense condition is attained at constant temperature. Numerical simulations are performed by presenting the densification of nano-particles at different deformations and distribution of dislocations. Finally, the evolutions of relative density with the pressure as well as the stress-strain curves are depicted during the compaction process. read less USED (low confidence) Y. Mahmood, M. S. Daw, M. Chandross, and F. Abdeljawad, “Universal trends in computed grain boundary energies of FCC metals,” Scripta Materialia. 2024. link Times cited: 0 USED (low confidence) S. Wang et al., “Effect of Electric Field on the Microstructure and Properties of NiAl Alloy Sheet Prepared by Foil Reaction Synthesis,” Journal of Materials Engineering and Performance. 2023. link Times cited: 0 USED (low confidence) G. Poletaev, Y. Bebikhov, and A. Semenov, “Molecular dynamics study of the formation of the nanocrystalline structure in nickel nanoparticles during rapid cooling from the melt,” Materials Chemistry and Physics. 2023. link Times cited: 1 USED (low confidence) Y. Xie, J.-L. Shao, R. Liu, and P. Chen, “Atomic insights into shock-induced alloying reaction of premixed Ni/Al nanolaminates.,” The Journal of chemical physics. 2023. link Times cited: 0 Abstract: In material processing and handling processes, premixed inte… read moreAbstract: In material processing and handling processes, premixed interlayer often replace the ideal Ni/Al interface, which would become a new origin of alloying reaction. This work investigates shock-induced reaction mechanism and kinetics of premixed Ni/Al nanolaminates with molecular dynamics simulations and theoretical analysis. The reaction is found to be driven by the crystallization evolution in premixed interlayer and the diffusion of premixed atoms. Among them, multi-stage reaction patterns are strongly manifested by the crystallization evolution characteristics. Specifically, "crystallization-dissolution-secondary growth" and "crystallization-dissolution" of B2 phase respectively correspond to the solid-state and solid-liquid reaction cases, where crystallizations are fitted well by Johnson-Mehl-Avrami kinetics model. Interestingly, the different growth mechanisms of B2 grain are revealed, namely nuclei coalescence and atomic diffusion. Moreover, the analysis of microscopic diffusion theory indicates a certain non-random diffusion nature for solid-state reaction initiation, but near-purely random diffusion for solid-liquid reaction initiation. The diffused Al atoms possess a limited diffusion coefficient and enhanced diffusion correlation, resulting in extremely slow mixing rate in Ni layer. In addition, the influence law of Ni concentration in premixed interlayer on reactivity parameters can be quantitatively described by a quadratic function. read less USED (low confidence) M. Chamani and G. H. Farrahi, “Multiscale modeling of nanoindentation and nanoscratching by generalized particle method.,” Journal of molecular graphics & modelling. 2023. link Times cited: 0 USED (low confidence) K. Zhu, Y. Xie, J.-L. Shao, and P. Chen, “Deformation, damage, and reaction characteristics during the collision between Ni and Al nanoparticles.,” Physical chemistry chemical physics : PCCP. 2023. link Times cited: 0 Abstract: The exothermic reaction during the collision between nanopar… read moreAbstract: The exothermic reaction during the collision between nanoparticles is of importance for the engineering applications of energetic powder materials. This work investigates collision-induced nanoparticle deformation, damage and reaction characteristics in a reactive Ni/Al system via molecular dynamics simulations. The morphological changes and reaction process are explored thoroughly for a wide range of impact velocities v and initial particle radius R. For lower impact velocities (1 km s-1 ≤ v ≤ 1.5 km s-1), the fully melted Al gradually clad the plastic deformed Ni nanoparticles to form an Al-shell/Ni-core structure, and the morphology ultimately develop into a nearly spherical shape possessing minimal surface energy. During this period, the self-sustaining reaction driven by the diffusion of Ni atoms into molten Al leads to slow melting of Ni nanoparticles, and the reaction and melting rates increase with the decrease of the particle radius. There exists one critical radius (R = 10 nm) beyond which the reaction is severely blocked due to the occurrence of fracture behavior at v = 1.5 km s-1. For intermediate velocities (2 km s-1 ≤ v < 3 km s-1), collision-induced debris clouds are observed, which satisfies the power-law distribution in the size of debris and results in an obvious reduction of the final reaction degree. Interestingly, we found that the reactive component in generated debris is lower for the larger-radius nanoparticle, which is also responsible for the lower final reaction degree and thermal kinetic energy. For higher velocities (v ≥ 3 km s-1), the occurrence of spallation damage reduces the contact area due to the formed micro-voids within Al and Ni nanoparticles and consequently the final reaction degree further. read less USED (low confidence) K. Noda and Y. Shibuta, “Prediction of potential energy profiles of molecular dynamic simulation by graph convolutional networks,” Computational Materials Science. 2023. link Times cited: 0 USED (low confidence) Y. Li, L. Zhang, W. Xiong, M. Tan, C. Liu, and X. Zhang, “Alloying reaction mechanism of shocked Ni/Al nanolaminates regulated via atomic diffusion,” Physics of Fluids. 2023. link Times cited: 0 Abstract: The Ni/Al nanolaminates represent cutting-edge functional ma… read moreAbstract: The Ni/Al nanolaminates represent cutting-edge functional materials that exhibit alloying reactions and release substantial energy when subjected to shock loading. However, the extremely short timeframes of the shock loading and the induced reactions surpass the resolving capability of state-of-the-art monitoring techniques, rendering the alloying reaction mechanism of Ni/Al nanolaminates a challenging multi-physical problem. To address this issue, we conducted extensive molecular dynamics simulations on large-scale models of Ni/Al nanolaminates at varying shock velocities to investigate their in situ thermodynamics response and shock-induced kinetic evolution related to phase transitions and chemical reactions. Our simulations revealed that atomic diffusion plays a pivotal role in accelerating the activation and intensifying the alloying reaction. For a self-sustaining reaction to occur, the shock-induced pressure must surpass a threshold, triggering global atomic diffusion that overcomes lattice trapping barriers or fluid viscosity, facilitating the formation of a sufficient number of Ni–Al intermetallic bonds to store energy. Subsequently, interfacial and bulk atomic diffusion becomes unstoppable, leading to a uniform distribution of mixed atoms and a steady energy release accompanied by continuous temperature rise, thereby triggering self-sustaining alloying reactions akin to an avalanche. Our findings not only offer a valuable baseline for understanding reactions in real defective composites but also establish a lower bound on the required shock intensity for future experiments using new high-quality samples. read less USED (low confidence) X. Qin, Y. Liang, and J. Gu, “Effects of Stress State, Crack—γ/γ′ Phase Interface Relative Locations and Orientations on the Deformation and Crack Propagation Behaviors of the Ni-Based Superalloy—A Molecular Dynamics Study,” Crystals. 2023. link Times cited: 0 Abstract: In this study, we systematically investigate the influence o… read moreAbstract: In this study, we systematically investigate the influence of stress states, relative locations, and orientations of crack—γ/γ′ phase interfaces on the deformation and crack propagation behaviors of the Ni-based superalloy through molecular dynamics simulations. The stress state with high stress triaxiality will impede the plastic deformation process of the system, thereby promoting brittle crack propagation within the system. But the stress state of low stress triaxiality results in obvious plastic deformation and plastic crack propagation behaviors of the system. The deformation system with cracks located in both the γ and γ′ phase exhibits the slowest growth rate, regardless of applied stress states. Additionally, the deformation process demonstrates prominent plastic behavior. For the deformation system with cracks perpendicular to the γ/γ′ phase interface, the γ/γ′ phase interface will hinder the crack propagation. Our research provides interesting observations on deformation and crack propagation behaviors at an atomic level and at a nano-scale which are important for understanding deformation and fracture behaviors at a macroscopic scale for the Ni-based superalloy. read less USED (low confidence) O. Politano and F. Baras, “Thermocapillary convection in a laser-heated Ni melt pool: A molecular dynamics study,” Journal of Applied Physics. 2023. link Times cited: 0 Abstract: Thermocapillary convection was investigated in a metallic sy… read moreAbstract: Thermocapillary convection was investigated in a metallic system of pure Ni, at the nanoscale, by molecular dynamics. The system interface was irradiated by a heat flux, mimicking a focused laser source. The melt pool was submitted to a large temperature gradient that modified the surface tension along the interface. In liquid metal, because surface tension typically decreases with increasing temperature, the result is a gradient of surface tension along the free surface. The liquid metal, therefore, started to flow in the direction of high surface tension. Two counter-rotating convection cells developed, characteristic of those observed in welding and other material processing. A systematic estimation of relevant parameters in hydrodynamics allowed us to interpret the results in terms of Prandtl, Marangoni, and Péclet numbers. This study demonstrates the influence of laser power and system size on pool shape and flow characteristics. read less USED (low confidence) Z. Zhang and C. Deng, “Hydrostatic pressure-induced transition in grain boundary segregation tendency in nanocrystalline metals,” Scripta Materialia. 2023. link Times cited: 0 USED (low confidence) L. Chalamet, D. Rodney, and Y. Shibuta, “Coarse-grained molecular dynamic model for metallic materials,” Computational Materials Science. 2023. link Times cited: 3 USED (low confidence) A. Moitra, “High temperature interfacial dynamics in Nickel coated Aluminum nanoparticles,” Computational Materials Science. 2023. link Times cited: 0 USED (low confidence) Q. Yin, J. D. Wang, Z. Wen, Q. Y. Shi, Y. Lian, and Z. Yue, “Creep-fatigue behavior of nickel-based single crystal superalloy with different orientations: Experimental characterization and multi-scale simulation,” Materials Science and Engineering: A. 2023. link Times cited: 0 USED (low confidence) L. Jiao et al., “Atomistic insights into the synergistic effect of nanotwins and nano-precipitates on the mechanical behavior of superalloys,” Mechanics of Materials. 2023. link Times cited: 0 USED (low confidence) F. Schwarz and R. Spolenak, “Mechanical behavior of reactive Al/Ni multilayers by molecular dynamics simulations,” Physical Review Materials. 2023. link Times cited: 0 USED (low confidence) F. Schwarz and R. Spolenak, “Shock compression of reactive Al/Ni multilayers—Phase transformations and mechanical properties,” Journal of Applied Physics. 2023. link Times cited: 2 Abstract: Reactive multilayers store large amounts of chemical energy,… read moreAbstract: Reactive multilayers store large amounts of chemical energy, which can be released through a self-sustaining reaction. One way of triggering the self-sustaining reaction is mechanical ignition, which is a prerequisite for designing a self-healing system. For potential integration into various devices, it is important to understand how Al/Ni reactive multilayers behave under shock compression. In this study, molecular dynamics (MD) simulations are employed to investigate Al/Ni reactive multilayers under shock compression. MD simulations allow for the understanding of what is happening at the atomistic level. Furthermore, they give access to bilayer heights that are difficult to study otherwise. This allows studying the shock wave propagation from bilayer heights of 100 down to 5 nm, while at the same time observing what is happening atomistically. Shock compression is studied both, for interfaces parallel and normal to the shock wave. It is shown that when the shock wave is parallel to the Al–Ni interfaces, there is a clear relationship between bilayer height and effective elastic modulus, which is not true when the interfaces are normal to the shock wave. Furthermore, intermixing of Al and Ni, as a prerequisite for ignition, strongly depends on the bilayer height as well as the impact velocity. Behind the shock wave, a phase transformation occurs, which strongly depends on the impact velocity, with a weak dependence on the bilayer height. Furthermore, void nucleation and fracture are observed, where the voids start nucleating in the Al layers. read less USED (low confidence) A. Hassani, A. Khmich, and A. Hasnaoui, “New approaches to study of mismatched interfaces structure on low-index surfaces by molecular dynamics simulation,” Applied Surface Science. 2023. link Times cited: 1 USED (low confidence) R. Rozas, J. L. Orrego, and P. Toledo, “Interfacial properties and crystal growth of Ni and Ni50Al50 from molecular dynamics simulations,” Journal of Applied Physics. 2023. link Times cited: 0 Abstract: Molecular dynamics simulations are used to determine the pro… read moreAbstract: Molecular dynamics simulations are used to determine the properties of the crystal–liquid interfaces of Ni and Ni50Al50. The interfacial free energies and kinetic growth coefficients for different crystal orientations are estimated using simulations of crystal–liquid systems at the melting temperature Tm from time- and wavenumber-dependent capillary wave height–height correlation functions. Growth coefficients are also determined from non-equilibrium simulations using the free solidification method, which compares well with those obtained from analysis of capillary wave fluctuations. Crystal growth in pure Ni is about a factor of 10 faster than in the binary Ni50Al50 system. The interfacial properties of the B2 intermetallic crystal phase of Ni50Al50 exhibit much lower anisotropy than those of the face-centered cubic crystalline structure of Ni. read less USED (low confidence) L. Ma, L. Zeng, C. Li, and W. Hu, “Effects of orientation on fatigue crack propagation of Ni3Al under super-gravity by molecular dynamics simulation,” AIP Advances. 2023. link Times cited: 0 Abstract: The effects of orientation on fatigue crack propagation of N… read moreAbstract: The effects of orientation on fatigue crack propagation of Ni3Al alloys under the super-gravity condition were studied by using the molecular dynamics method. The research found that the crack initiation and propagation mechanisms were different for different orientation crack models: the [001](010) crack germinated in the form of blunting damage and voids and the [1̄10](110) crack began initiation as blunting damage and slip bands. For the [112̄](111) crack, the initiation mechanisms of the crack were the same as the [1̄10](110) crack. In the crack propagation stage, the main deformation mechanisms of all crack models were slip bands, but the slip directions were different: the [001](010) crack and [112̄](111) crack presented ductile cracking and the [1̄10](110) crack presented brittleness fracture. Then, the crack growth rate and stress intensity factor were also analyzed under the super-gravity condition. The results showed that the [112̄](111) crack had the slowest growth rate compared to other two cracks under the super-gravity condition, and the [112̄](111) crack had the maximum stress intensity factor variable at initiation, but the variation tendency of stress intensity factors was slowest for the [112̄](111) crack under the super-gravity condition. read less USED (low confidence) A. Khoei, H. Mofatteh, and A. R. Sameti, “A multiscale framework for atomistic–continuum transition in nano-powder compaction process using a cap plasticity model,” International Journal of Mechanical Sciences. 2023. link Times cited: 2 USED (low confidence) Y. Xie, J. Shao, R. Liu, and P. Chen, “The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading,” Defence Technology. 2023. link Times cited: 0 USED (low confidence) H. Mes-adi, R. Herbazi, M. Lablali, K. Saadouni, and M. Mazroui, “NiAl (0 0 1) terminated surface effect on the growth of the Al thin film,” Computational Materials Science. 2023. link Times cited: 3 USED (low confidence) W. Wu, Z. Ding, Y.-li Li, C. Yu, and G. Kang, “Molecular dynamics simulation of thermomechanical fatigue properties of Ni-based single crystal superalloys,” International Journal of Fatigue. 2023. link Times cited: 0 USED (low confidence) W. Du, X. Fan, H. Li, D. Zhai, and Y. Liu, “Development of a Ni-Al Reactive Force Field for Ni-Based Superalloy: Revealing Electrostatic Effects on Mechanical Deformation,” SSRN Electronic Journal. 2023. link Times cited: 0 USED (low confidence) J. Wen, J.-Y. Sun, B. Du, Y. Chen, and X. Yan, “The Interfacial Stability of Single Crystal Superalloy Affected by the Phase Structure of the Ni-Al Coating,” SSRN Electronic Journal. 2023. link Times cited: 1 USED (low confidence) S. M. Estalaki, T. Luo, and K. Manukyan, “Bayesian optimization of metastable nickel formation during the spontaneous crystallization under extreme conditions,” Journal of Applied Physics. 2023. link Times cited: 0 Abstract: Spontaneous crystallization of metals under extreme conditio… read moreAbstract: Spontaneous crystallization of metals under extreme conditions is a unique phenomenon occurring under far-from-equilibrium conditions that could enable the development of revolutionary and disruptive metastable metals with unusual properties. In this work, the formation of the hexagonal close-packed nickel (hcp-Ni) metastable phase during spontaneous crystallization is studied using non-equilibrium molecular dynamics (MD) simulations, with the goal of maximizing the fraction of this metastable phase in the final state. We employ Bayesian optimization (BO) with the Gaussian processes (GPs) regression as the surrogate model to maximize the hcp-Ni phase fraction, where temperature and pressure are control variables. MD simulations provide data for training the GP model, which is then used with BO to predict the next simulation condition. Such BO-guided active learning leads to a maximum hcp-Ni fraction of 43.38% in the final crystallized phase within 40 iterations when a face-centered cubic crystallite serves as the seed for crystallization from the amorphous phase. When an hcp seed is used, the maximum hcp-Ni fraction in the final crystal increases to 58.25% with 13 iterations. This study shows the promise of using BO to identify the process conditions that can maximize the rare phases. This method can also be generally applicable to process optimization to achieve target material properties. read less USED (low confidence) G. T. Eshlaghi and A. Khoei, “Modeling anisotropic mechanical properties and creep behavior of Ni($γ)/Ni3Al(γ’$) single crystal superalloys at high temperatures,” Journal of Nanoparticle Research. 2023. link Times cited: 0 USED (low confidence) H. Dong et al., “Atomic simulations on the deformation mechanisms in nano-crystalline Ni–Al series Ni-based superalloy based on grain size, strain rate and temperature,” Journal of Materials Research and Technology. 2023. link Times cited: 3 USED (low confidence) E. Yousefi et al., “Dynamics of intermetallics formation in the Al/Ni reactive wetting system,” Materialia. 2023. link Times cited: 1 USED (low confidence) F. Wang, L. Li, H. Tang, X. Wang, and Y. Hu, “Damping of aluminum-matrix composite reinforced by carbon nanotube: Multiscale modeling and characteristics,” Science China Technological Sciences. 2023. link Times cited: 4 USED (low confidence) N. Tuchinda and C. Schuh, “Triple junction solute segregation in Al-based polycrystals,” Physical Review Materials. 2023. link Times cited: 3 USED (low confidence) B. Chen, Y.-li Li, D. Şopu, J. Eckert, and W. Wu, “Molecular dynamics study of shock-induced deformation phenomena and spallation failure in Ni-based single crystal superalloys,” International Journal of Plasticity. 2023. link Times cited: 10 USED (low confidence) B. Waters, D. S. Karls, I. Nikiforov, R. Elliott, E. Tadmor, and B. Runnels, “Automated determination of grain boundary energy and potential-dependence using the OpenKIM framework,” Computational Materials Science. 2022. link Times cited: 5 USED (low confidence) T. He, H. Xie, G. Wei, and G. Lu, “An atomistic study of the thermal and anti-thermal behavior of incoherent twin step migration under an elastic energy driving force,” Computational Materials Science. 2022. link Times cited: 1 USED (low confidence) J. Zhou, Y. Yang, and Y. Yu, “Revealing mechanical property–strengthening micro-mechanism of Ni/Ni3Al-based alloys by molecular dynamics simulation,” Journal of Molecular Modeling. 2022. link Times cited: 1 USED (low confidence) L. Ma, S. Peng, C. Li, and W. Hu, “Atomic simulation of effects of Ʃ5 grain boundary on mechanical properties of Ni3Al,” The European Physical Journal B. 2022. link Times cited: 0 USED (low confidence) L. E. Kar’kina, I. N. Kar’kin, and Y. Gornostyrev, “The Formation of Segregations and Nanofaceting of Asymmetric Special Grain Boundaries in Al,” Physics of Metals and Metallography. 2022. link Times cited: 0 USED (low confidence) M. Chamani, “Three-dimensional multiscale modeling of nanoindentation.,” Journal of molecular graphics & modelling. 2022. link Times cited: 1 USED (low confidence) F. Li et al., “The EIFS-based Fatigue Life Prediction Approach of Nickel-based Single Crystals with Film Cooling Holes at Elevated Temperature,” International Journal of Fatigue. 2022. link Times cited: 3 USED (low confidence) F. Schwarz and R. Spolenak, “An MD-study on changing the elemental distribution and composition by alloying to control front propagation in Al–Ni multilayers,” Journal of Applied Physics. 2022. link Times cited: 3 Abstract: To cover the wide range of applications of reactive multilay… read moreAbstract: To cover the wide range of applications of reactive multilayers, it is necessary to have the ability to vary and control their front propagation velocities as well as their maximum reaction temperatures. In this paper, Molecular Dynamics simulations are used to study the influence of Al alloying, Ni alloying, and Co alloying on Al–Ni multilayers. In the case of alloying with Al and Ni, the iso-stoichiometric case where both the Al and the Ni layers are alloyed is first studied. In the second step, the stoichiometry is varied by alloying only one of the two layers with the other element. This allows for achieving very small front propagation velocities. Furthermore, the Ni layer is alloyed with Co and the whole range from a binary Al–Ni to the binary Al–Co system is studied. The front propagation velocity does not change linearly with the alloying fraction and reaches a minimum where the Ni/Co alloy changes from a face centered cubic to a hexagonal close packed lattice. read less USED (low confidence) S. Kolli et al., “Fracture mechanisms of Ni-Al interfaces – A nanoscale view,” Materials Today Communications. 2022. link Times cited: 1 USED (low confidence) M. Zakaryan et al., “Spontaneous Crystallization for Tailoring Polymorphic Nanoscale Nickel with Superior Hardness,” The Journal of Physical Chemistry C. 2022. link Times cited: 2 USED (low confidence) L. Ma, P. Fei, C. Li, and W. Hu, “Analysis of fatigue crack propagation mechanism of Ni3Al under supergravity at atomic size,” AIP Advances. 2022. link Times cited: 1 Abstract: Mechanisms of fatigue crack propagation of Ni3Al alloy under… read moreAbstract: Mechanisms of fatigue crack propagation of Ni3Al alloy under supergravity are studied by the molecular dynamics method. The initial model of the crack is a [100](010) crack in Ni3Al. Changes in the microstructure evolution, crack growth rate, and stress intensity factor of [100](010) crack are compared and analyzed without and with supergravity. The results show that the deformation mechanisms of the crack tip are slip bands along the a/6[112] direction by dislocation analysis in the absence of supergravity cyclic loading; after adding to supergravity, the mechanisms of crack propagation have changed, multiple voids are formed at the crack tip, and the dislocation lines also grow faster, which cause severe damage to the internal structure of the [100](010) crack in Ni3Al. By tracking the changes in crack length and width, it is found that the supergravity accelerates the growth of crack length and width and reduces the stress intensity factor threshold. Finally, the crack propagation rate increases under supergravity conditions. read less USED (low confidence) W. Wu, Z. Ding, B. Chen, H. Shen, and Y.-li Li, “Effect of rhenium on low cycle fatigue behaviors of Ni-based single crystal superalloys: A molecular dynamics simulation,” Journal of Materials Research and Technology. 2022. link Times cited: 3 USED (low confidence) Y. Huang, H. Chen, D. Li, R. Zhou, and B. Zhang, “The relationship between inter-diffusion and self-diffusion of different liquid metals studied by molecular dynamics simulations,” Physica B: Condensed Matter. 2022. link Times cited: 0 USED (low confidence) Y. Xie, J. Shao, R. Liu, and P. Chen, “Chemical reaction of Ni/Al interface associated with perturbation growth under shock compression,” Physics of Fluids. 2022. link Times cited: 7 Abstract: The exothermic reaction of Ni/Al laminates always starts fro… read moreAbstract: The exothermic reaction of Ni/Al laminates always starts from the interface, and the role of interfacial instability in the shock-induced chemical reaction has not been clarified. This work reports the Richtmyer–Meshkov (RM) instability growth, atomic diffusion, and chemical reaction of Ni/Al interface under shock compression based on atomistic simulations. For shocking from Al to Ni, the interface experiences finite collapse and exhibits weak localized reaction. The diffusion of solid Ni to molten Al will be inhibited due to the formation of NiAl phase, and continuous inter-diffusion occurs with the melting of Ni. For shocking from Ni to Al, a small amount of NiAl structure is formed due to the atomic residue during defect collapse. RM instability growth is observed at higher shock intensity, which significantly promotes the atomic mixing and results in a power-law increase in the number of diffusing atoms. Meanwhile, the chemical reaction propagates rapidly from the vortex to the head of the spike accompanied by the decomposition of many clusters, with the nonlinear development of RM instability. The number and the size of Ni clusters no more satisfy the simple power-law relationship for which we propose an improved power-law distribution. Interestingly, the growth of nanoscale perturbation approximately satisfies the logarithmic law with time, but the linear growth stage is inhibited due to significant inter-diffusion, especially for the small wavelength. Thus, the mixing width and the reaction degree are positively correlated with the initial wavelength in our simulation scale, which is contrary to the RM growth law of the free surface. read less USED (low confidence) A. Abu-Odeh, D. Olmsted, and M. Asta, “Screw dislocation mobility in a face-centered cubic solid solution with short-range order,” Scripta Materialia. 2022. link Times cited: 5 USED (low confidence) F. Schwarz and R. Spolenak, “The influence of premixed interlayers on the reaction propagation in Al–Ni multilayers —An MD approach,” Journal of Applied Physics. 2022. link Times cited: 9 USED (low confidence) B. Chen, W. Wu, and M. Chen, “Orientation dependence of microstructure deformation mechanism and tensile mechanical properties of Nickel-based single crystal superalloys: A molecular dynamics simulation,” Computational Materials Science. 2022. link Times cited: 5 USED (low confidence) A. Daramola, G. Bonny, G. Adjanor, C. Domain, G. Monnet, and A. Fraczkiewicz, “Development of a plasticity-oriented interatomic potential for CrFeMnNi high entropy alloys,” Computational Materials Science. 2022. link Times cited: 4 USED (low confidence) S. Starikov, A. R. Kuznetsov, and V. Sagaradze, “Crowdion in Deformed FCC Metal. Atomistic Modeling,” Physics of Metals and Metallography. 2021. link Times cited: 3 USED (low confidence) A. Abu-Odeh and M. Asta, “Modeling the Effect of Short-Range Order on Cross-Slip in an FCC Solid Solution,” Acta Materialia. 2021. link Times cited: 11 USED (low confidence) J. Feng et al., “Shock Consolidation of Ni/Al Nanoparticles: A Molecular Dynamics Simulation,” Journal of Materials Engineering and Performance. 2021. link Times cited: 3 USED (low confidence) L. Wang, J. Zhou, H. Liu, and F. Zhang, “Severe grain rotation behavior of L12-B2 nano lamellar eutectic structure,” Materials Letters. 2021. link Times cited: 1 USED (low confidence) B. Chen and W. Wu, “Molecular dynamics simulations of dynamics mechanical behavior and interfacial microstructure evolution of Ni-based single crystal superalloys under shock loading,” Journal of Materials Research and Technology. 2021. link Times cited: 15 USED (low confidence) Q. Yin, Y. Lian, Z. Wen, H. Pei, J. Wang, and Z. Yue, “Atomic simulation of the effect of orientation on tensile/compressive properties in nickel-based single crystal superalloys,” Journal of Alloys and Compounds. 2021. link Times cited: 17 USED (low confidence) F. Schwarz and R. Spolenak, “Molecular dynamics study of the influence of microstructure on reaction front propagation in Al–Ni multilayers,” Applied Physics Letters. 2021. link Times cited: 7 Abstract: Reactive multilayers can be used for energy storage as well … read moreAbstract: Reactive multilayers can be used for energy storage as well as releasing large amounts of heat in a short time. Molecular Dynamics (MD) simulations are used to study the influence of the crystal structure on the reaction front propagation in Al–Ni multilayers. Different microstructures, namely, amorphous, single crystal, columnar grains, and randomly oriented grains of varying size, are investigated. The effect of the microstructure on the propagation speed is studied and compared to existing experimental results. Furthermore, MD simulations allow to study the inter-diffusion of the Al and Ni layers. It is found that crystallinity has a significant impact on the front propagation speed, which is likely related to different diffusion mechanisms. The more disordered the individual layers become, e.g., by increasing the grain boundary density, the higher is the resulting propagation speed. read less USED (low confidence) M. Wagih and C. Schuh, “Thermodynamics and design of nanocrystalline alloys using grain boundary segregation spectra,” Acta Materialia. 2021. link Times cited: 20 USED (low confidence) X. Tian, M. Xiang, J. Cui, G. Ji, and Z. Fu, “Spalling fracture of Ni/Al nanolaminates influenced by chemical reaction,” Journal of Applied Physics. 2021. link Times cited: 3 Abstract: We investigate spalling behaviors of Ni/Al nanolaminates by … read moreAbstract: We investigate spalling behaviors of Ni/Al nanolaminates by molecular dynamics simulations. First, we discuss spalling damage distributions in shocked Ni/Al nanolaminates. Voids nucleate in Al layers, while no voids are located in Ni layers or along the Ni/Al interfaces. This is because the spall strength of single-crystalline Ni is higher than that of single-crystalline Al. We reveal influences of a shock-induced chemical reaction on dynamic spalling damage and fracture processes. An abnormal “decrease → increase → decrease” zigzag variation tendency of the spall strength of Ni/Al nanolaminates as the impact velocity increase is observed in our simulations, which resulted from combining effects of micro-structures, chemical reactions, and temperature softening. When the impacting intensity is relatively low, the spall strength of Ni/Al nanolaminates decreases as the impact velocity increases due to micro-structure effects. However, when the loading velocity increases to a certain magnitude (2.5 km/s), the intimate contact of liquid Al with amorphous Ni near the interface makes the chemical reaction rate increase rapidly to form a large amount of Ni/Al alloys and enhances the spall strength. read less USED (low confidence) A. Z. Mani, U. B. Jayadeep, and R. Ramaseshan, “Molecular dynamics simulation of indentation on nanocoated surfaces: A comparison between 3D and 2D plane strain models,” Journal of Materials Research. 2021. link Times cited: 4 Abstract: Molecular dynamics studies with 3D model using spherical ind… read moreAbstract: Molecular dynamics studies with 3D model using spherical indenter and 2D plane strain model using cylindrical indenters revealed that the optimum coating thickness maximizing the hardness for a single layered nanocoating lies between 15 nm and 20 nm. The computational time is significantly lower for the plane strain model using cylindrical indenter than for the spherical indenter. However, the calculated hardness is different in both cases due to continuum and non-continuum effects. Continuum effects result in a reduction of hardness calculated by a cylindrical indenter, while the non-continuum effects result in an increase. read less USED (low confidence) F. Baras, Q. Bizot, A. Fourmont, S. L. Gallet, and O. Politano, “Mechanical activation of metallic powders and reactivity of activated nanocomposites: a molecular dynamics approach,” Applied Physics A. 2021. link Times cited: 1 USED (low confidence) Q. Yang, H. Liu, and H. Peng, “Crystal growth in deeply undercooled Ni50Al50: Signature of the ordering sequence at the interface.,” The Journal of chemical physics. 2021. link Times cited: 7 Abstract: Crystal growth of the intermetallic alloy, Ni50Al50, is inve… read moreAbstract: Crystal growth of the intermetallic alloy, Ni50Al50, is investigated by molecular dynamics simulations with two different interatomic potentials. The calculated growth rate can be captured by the Wilson-Frenkel or Broughton-Gilmer-Jackson model at small undercoolings but deviates from the theory at deep undercoolings. Failure of the theory is found to be correlated with the dynamic processes that emerged at the interface, but not apparently with the static interface structure. The chemical segregation of Ni and Al atoms occurs before the geometrical ordering upon crystallization at small undercoolings. In contrast, the geometrical ordering precedes the chemical one at deep undercoolings. These two ordering processes show a collapsed time evolution at the crossover temperature consistent with the onset of the theoretical deviation. We rationalize the delayed chemical segregation behavior by the collective atomic motion, which is characterized by the super-Arrhenius transition of the temperature-dependent diffusivity and structural relaxation time at the crossover point. read less USED (low confidence) Q. Yin, Y. Lian, R. Wu, L. Gao, S.-Q. Chen, and Z. Wen, “Effect of the potential function and strain rate on mechanical behavior of the single crystal Ni-based alloys: A molecular dynamics study*,” Chinese Physics B. 2021. link Times cited: 1 USED (low confidence) S. Zhao and Y. Osetsky, “Structural and chemical disorder enhance point defect diffusion and atomic transport in Ni3Al-based γ′ phase,” Acta Materialia. 2021. link Times cited: 11 USED (low confidence) J. F. Hickman, Y. Mishin, V. Ozoliņš, and A. Ardell, “Coarsening of solid
β
-Sn particles in liquid Pb-Sn alloys: Reinterpretation of experimental data in the framework of trans-interface-diffusion-controlled coarsening,” Physical Review Materials. 2021. link Times cited: 3 Abstract: James F. Hickman,1 Yuri Mishin ,2 Vidvuds Ozoliņš ,3 and Ala… read moreAbstract: James F. Hickman,1 Yuri Mishin ,2 Vidvuds Ozoliņš ,3 and Alan J. Ardell 4,* 1Materials Science and Engineering Division, National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899-8910, USA 2Department of Physics and Astronomy, George Mason University, Fairfax, Virginia 22030-4444, USA 3Department of Applied Physics, Energy Sciences Institute, Yale University, New Haven, Connecticut 06511, USA 4Department of Materials Science and Engineering, UCLA Samueli School of Engineering, Los Angeles, California 90095-1595, USA read less USED (low confidence) A. Khoei, G. T. Eshlaghi, and S. Shahoveisi, “Atomistic simulation of creep deformation mechanisms in nickel-based single crystal superalloys,” Materials Science and Engineering A-structural Materials Properties Microstructure and Processing. 2021. link Times cited: 24 USED (low confidence) S. Gowthaman and T. Jagadeesha, “Effect of cross section and temperature on the Ni3Al precipitate on the tensile behavior through molecular dynamics simulation,” Materials Today: Proceedings. 2021. link Times cited: 1 USED (low confidence) O. Politano, A. Rogachev, and F. Baras, “Molecular Dynamics Studies in Nanojoining: Self-Propagating Reaction in Ni/Al Nanocomposites,” Journal of Materials Engineering and Performance. 2021. link Times cited: 3 USED (low confidence) L.-F. Zhu, J. Janssen, S. Ishibashi, F. Körmann, B. Grabowski, and J. Neugebauer, “A fully automated approach to calculate the melting temperature of elemental crystals,” Computational Materials Science. 2021. link Times cited: 17 USED (low confidence) C. Niu et al., “Surface modification and structure evolution of aluminum under argon ion bombardment,” Applied Surface Science. 2021. link Times cited: 10 USED (low confidence) M. He, E. T. Karim, M. Shugaev, and L. Zhigilei, “Atomistic simulation of the generation of vacancies in rapid crystallization of metals,” Acta Materialia. 2021. link Times cited: 7 USED (low confidence) B. Chen, W. Wu, M. Chen, and Y.-F. Guo, “Molecular dynamics study of fatigue mechanical properties and microstructural evolution of Ni-based single crystal superalloys under cyclic loading,” Computational Materials Science. 2020. link Times cited: 26 USED (low confidence) S. Zhao, D. Chen, G. Yeli, and J. Kai, “Atomistic insight into the effects of order, disorder and their interface on defect evolution,” Journal of Alloys and Compounds. 2020. link Times cited: 8 USED (low confidence) T. Fukuya and Y. Shibuta, “Machine learning approach to automated analysis of atomic configuration of molecular dynamics simulation,” Computational Materials Science. 2020. link Times cited: 12 USED (low confidence) P. Yi, D. Ruan, T. Weihs, and M. Falk, “Predicting the Rate of Homogeneous Intermetallic Nucleation within Steep Composition Gradients,” Journal of Physical Chemistry C. 2020. link Times cited: 2 Abstract: Simulations of isothermal homogeneous nucleation from deeply… read moreAbstract: Simulations of isothermal homogeneous nucleation from deeply undercooled amorphous melts exhibit systematic variations in nucleation behavior depending upon the strength of an imposed composition g... read less USED (low confidence) J. Ding et al., “Multi-scale numerical simulation of fracture behavior of nickel-aluminum alloy by coupled molecular dynamics and cohesive finite element method (CFEM),” Theoretical and Applied Fracture Mechanics. 2020. link Times cited: 13 USED (low confidence) H. P. Zhang, B. Fan, J. Wu, W. Wang, and M. Li, “Universal relationship of boson peak with Debye level and Debye-Waller factor in disordered materials,” Physical Review Materials. 2020. link Times cited: 4 Abstract: Due to the topological disorder, glass displays an anomalous… read moreAbstract: Due to the topological disorder, glass displays an anomalous vibrational density of states beyond the Debye model, i.e., formation of boson peaks, which is fundamental for understanding many glassy physical properties. However, the understanding of the boson peak remains notoriously complex and is a topic of hot debate. Here we report a universal quantitative relation between boson peak intensity and the Debye level of transverse phonons in different glasses, confirming the intrinsic link between boson peaks and transverse phonons. Moreover, an equation is derived for the boson peak intensity and Debye-Waller factor, indicating that boson peaks are fundamentally determined by the Debye-Waller factor. These findings could clarify some controversial issues and reveal a common basis for high-frequency boson peak dynamics $(\ensuremath{\sim}{10}^{12}\phantom{\rule{0.28em}{0ex}}\mathrm{Hz})$, short-time $\ensuremath{\beta}$ processes $({10}^{3}\ensuremath{\sim}{10}^{6}\phantom{\rule{0.28em}{0ex}}\mathrm{Hz})$, and long-time $\ensuremath{\alpha}$ processes $({10}^{\ensuremath{-}4}\ensuremath{\sim}{10}^{3}\phantom{\rule{0.28em}{0ex}}\mathrm{Hz})$ in disordered materials. read less USED (low confidence) G. Naresh and G. Rajasekaran, “Characterization and Applications of Titanium alloy with Nickel and Niobium based Shape memory alloys by Molecular Dynamic Simulation–A review,” IOP Conference Series: Materials Science and Engineering. 2020. link Times cited: 0 Abstract: Characterization of Shape memory alloys using simulations li… read moreAbstract: Characterization of Shape memory alloys using simulations like molecular dynamics (MD) approach is a difficult but at the same time it is an effective process. In this article, recent works on MD simulation of titanium-based shape memory alloys which can be used as nano sensors for sensing various properties like temperature, pressure and relative humidity were discussed. The accuracy of MD simulation is based on potentials like modified embedded atom method to study its mechanical behavior at different temperatures in atomic scale. Also, the force between individual particles of the alloy was calculated to determine the mechanical properties of shape memory alloys depending on the interparticle free space. Hence in this article authors were discussed various types of potentials and its effectiveness to characterize mechanical properties. Also, this article gives an overview of Nickel and Niobium based titanium alloy on various application. read less USED (low confidence) L. E. Kar’kina, I. N. Kar’kin, and Y. Gornostyrev, “Effect of Alloying Element Segregations on the Grain Boundary Sliding in Al–Mg and Al–Ni Alloy Bicrystals: Atomistic Modeling,” Physics of Metals and Metallography. 2020. link Times cited: 5 USED (low confidence) H. E. Azrak, A. Hassani, K. Sbiaai, and A. Hasnaoui, “NiAl thin film growth on Ni(001) substrate using molecular dynamics simulations,” European Physical Journal-applied Physics. 2020. link Times cited: 2 Abstract: We have studied thin film growth of NiAl on Nickel (001) sub… read moreAbstract: We have studied thin film growth of NiAl on Nickel (001) substrate using molecular dynamics simulations (MD) based on the Embedded Atom Method (EAM) potential. An incidence energy of 0.06 eV at 800 K, 900 K and 1000 K was considered. After the deposition process, we have obtained a B2-NiAl structure film with different percentages; 32.6% for the temperature 1000 K, 30% for 900 K and 25% for 800 K. Our investigation has prompt us to analyze the crystalline structure. During the evolution of deposited film, we observe the formation of grains with different orientation, as well as the appearance of vacancies in Ni and Al sublattices and antisites. read less USED (low confidence) S. Nag and W. Curtin, “Effect of solute-solute interactions on strengthening of random alloys from dilute to high entropy alloys,” Acta Materialia. 2020. link Times cited: 28 USED (low confidence) A. Khoei, A. R. Sameti, and H. Mofatteh, “Compaction simulation of crystalline nano-powders under cold compaction process with molecular dynamics analysis,” Powder Technology. 2020. link Times cited: 20 USED (low confidence) N. Kaur, C. Deng, and O. Ojo, “Effect of solute segregation on diffusion induced grain boundary migration studied by molecular dynamics simulations,” Computational Materials Science. 2020. link Times cited: 12 USED (low confidence) M. Ghaemi and R. Tavakoli, “Universal correlation between the thermodynamic potentials and some physical quantities of metallic glasses as a function of cooling rate during molecular dynamics simulation,” Journal of Non-crystalline Solids. 2020. link Times cited: 2 USED (low confidence) H. E. Azrak, A. Hassani, K. Sbiaai, and A. Hasnaoui, “Investigating the potentialities of Ni3Al alloy formation on Ni substrates: Molecular dynamics simulation,” Journal of Crystal Growth. 2020. link Times cited: 8 USED (low confidence) H. Yang, L. Zhu, R. Zhang, J. Zhou, and Z. Sun, “Influence of high stacking-fault energy on the dissociation mechanisms of misfit dislocations at semi-coherent interfaces,” International Journal of Plasticity. 2020. link Times cited: 9 USED (low confidence) M. Moradi, G. Farrahi, and M. Chamani, “Effect of microstructure on crack behavior in nanocrystalline nickel using molecular dynamics simulation,” Theoretical and Applied Fracture Mechanics. 2019. link Times cited: 6 USED (low confidence) S. Yalameha and A. Vaez, “Structural, electronic, elastic and thermodynamic properties of Al1-Z Ni (Z=Cr, V and x= 0, 0.125, 0.25) alloys: First-principle calculations,” Computational Condensed Matter. 2019. link Times cited: 14 USED (low confidence) H. Peng et al., “Chemical effect on the structural and dynamical properties in Zr-Ni-Al liquids,” Physical Review B. 2019. link Times cited: 9 Abstract: We develop an embedded-atom method (EAM) model to perform cl… read moreAbstract: We develop an embedded-atom method (EAM) model to perform classical molecular-dynamics computer simulations of a model of Zr-Ni-Al ternary melts, based on the existing binary ones. The EAM potential is validated against a broad range of experimental data for the liquid melt, including both static-structure factors and dynamical data on the mass-transport coefficients. We use our simulation model to address the structural and dynamical changes induced by a systematic replacement of Zr by Al in ${\mathrm{Zr}}_{75\ensuremath{-}x}{\mathrm{Ni}}_{25}{\mathrm{Al}}_{x}\phantom{\rule{4pt}{0ex}}(x=0--30)$ ternary alloys. We find strong chemical-ordering effects exhibited as the locally preferred structure when the Al-concentration ${c}_{\text{Al}}$ is increased. Along with the chemical effects, effective-power-law relations are found between the self-diffusion coefficients in the melts, with an exponent that monotonically decreases with increasing Al concentration. The associated Stokes-Einstein relation between diffusivity and viscosity breaks down at higher temperature upon Al addition. We also address the influence of Al admixture on the vibrational spectrum of the melt. With increasing ${c}_{\text{Al}}$, sound waves move faster, and an optical vibrational mode is found. read less USED (low confidence) S. L. Thomas, J. Han, and D. Srolovitz, “The Coupling of Grain Growth and Twinning in FCC Metals,” IOP Conference Series: Materials Science and Engineering. 2019. link Times cited: 2 Abstract: Coherent twin boundaries (CTBs) routinely form during the an… read moreAbstract: Coherent twin boundaries (CTBs) routinely form during the annealing of polycrystalline metals, in the absence of an applied stress. Molecular dynamics (MD) simulations of normal grain growth in nanocrystalline metals show such annealing twins as well the formation of twin junctions. MD simulations and theoretical analyses demonstrate how these junctions form and that their formation necessarily retards grain boundary (GB) migration. Both CTB and GB migration occurs via disconnection motion. We identify the types of disconnections important for CTB migration and show the disconnection pile-ups at TJs during GB migration are responsible for CTB formation in the vicinity of TJs. Analysis further shows that at least two types twinning partials are to be expected during TJ migration and that these give rise to the multiple twinning near migrating TJs observed in the MD simulations. read less USED (low confidence) I. Belova et al., “Computer simulation of thermodynamic factors in Ni-Al and Cu-Ag liquid alloys,” Computational Materials Science. 2019. link Times cited: 4 USED (low confidence) J. Wang, J. Liang, Z. Wen, and Z. Yue, “Atomic simulation of void location effect on the void growth in nickel-based single crystal,” Computational Materials Science. 2019. link Times cited: 17 USED (low confidence) D. Zhang and S. Chaudhuri, “Solidification dynamics and microstructure evolution in nanocrystalline cobalt,” Computational Materials Science. 2019. link Times cited: 8 USED (low confidence) M. Settem, “On the structural analysis of ordered B2 AlNi nanoparticles obtained using freezing simulations,” Intermetallics. 2019. link Times cited: 2 USED (low confidence) A. Hassani et al., “Statistical investigations of the film-substrate interface during aluminum deposition on Ni(111) by molecular dynamics simulation,” Superlattices and Microstructures. 2019. link Times cited: 9 USED (low confidence) S. Nosewicz, J. Rojek, K. Wawrzyk, P. Kowalczyk, G. Maciejewski, and M. Maździarz, “Multiscale modeling of pressure-assisted sintering,” Computational Materials Science. 2019. link Times cited: 13 USED (low confidence) D. Fleita, G. Norman, and V. Pisarev, “Collective effects and liquid–glass transition in supercooled melts of binary alloys,” Journal of Physics: Conference Series. 2019. link Times cited: 3 Abstract: A possibility of a transition into a glassy state of binary … read moreAbstract: A possibility of a transition into a glassy state of binary alloys based on aluminum, nickel, and copper after ultrafast cooling has been investigated using the method of molecular dynamics. It was demonstrated that some 4-point correlators changed their behavior and depended on the parameters of the metastable alloy state. By analyzing the complex dynamics of particle motion in overcooled liquids some certain conditions for the formation of the glass for aluminum–nickel melt was founded. read less USED (low confidence) H. Fan, A. Ngan, K. Gan, and J. El-Awady, “Origin of double-peak precipitation hardening in metallic alloys,” International Journal of Plasticity. 2018. link Times cited: 44 USED (low confidence) N. T. Trung, H. Phuong, M. Starostenkov, V. Romanenko, and V. Popov, “Threshold displacement energy in Ni, Al and B2 NiAl,” IOP Conference Series: Materials Science and Engineering. 2018. link Times cited: 18 Abstract: For simulation of radiation effects and defects in the Ni-Al… read moreAbstract: For simulation of radiation effects and defects in the Ni-Al system, a new many body potential was developed by joining the equilibrium part of the Mishin’s EAM potential with the universal function of Ziegler, Biersack and Littmark at a suitable interatomic spacing and the corresponding pairwise energy from the DFT calculations. To assess the qualities of this potential, we performed molecular dynamics simulations to calculate the threshold displacement energy of pure metals Ni, Al and their NiAl B2 phase superalloy at ambient temperature. It was found that the threshold energy of displacement of nickel in nickel is higher than that in the B2 long-range ordered alloy NiAl in contrast to aluminium, which has lower threshold energy than B2 NiAl. The threshold displacement energy ranges between 14±2 eV and 189±2 eV depending on the crystallographic direction. The lowest threshold energy of two fcc metals (14±2 eV for Al and 28±2 eV for Ni) was found in the direction <101>, these values correspond to the mean value in the easiest directions of atomic displacements and they are in good agreement with many reports from the literature. read less USED (low confidence) H. Kondo, M. Wakeda, and I. Watanabe, “Atomic study on the interaction between superlattice screw dislocation and γ-Ni precipitate in γ′-Ni3Al intermetallics,” Intermetallics. 2018. link Times cited: 10 USED (low confidence) G. D. Smith, J. Hooper, and D. Bedrov, “Mesoscale simulations of uniaxial compression and shock loading of low porosity granular aluminum/nickel composites,” Journal of Applied Physics. 2018. link Times cited: 3 Abstract: Continuum level Material Point Method (MPM) simulations have… read moreAbstract: Continuum level Material Point Method (MPM) simulations have been carried out on low porosity (around 90% or greater of theoretical maximum density) microstructures of Al/Ni granular composites (Al/Ni). The Al/Ni microstructures were subjected to uniaxial (strain) compressive loading and shock compression up to 25 GPa. The MPM model accounted for frictional heating between grains in addition to plastic work and compressional heating effects. The distributions of stresses and temperature in the composite materials were found to be highly heterogeneous due to the heterogeneous nature of the composite microstructure. The manner in which interfaces between grains were treated (sliding vs. non-sliding) was found to influence both mechanical and thermal responses to loading. Plastic deformation, mechanical work, and grain/grain frictional effects led to modest increases of mean temperature and local hotspots with maximum temperature not higher than 800–850 K for loadings investigated. For all scenarios investigated, heat generation was insufficient to cause local Al melting believed to be a precursor for shock initiation.Continuum level Material Point Method (MPM) simulations have been carried out on low porosity (around 90% or greater of theoretical maximum density) microstructures of Al/Ni granular composites (Al/Ni). The Al/Ni microstructures were subjected to uniaxial (strain) compressive loading and shock compression up to 25 GPa. The MPM model accounted for frictional heating between grains in addition to plastic work and compressional heating effects. The distributions of stresses and temperature in the composite materials were found to be highly heterogeneous due to the heterogeneous nature of the composite microstructure. The manner in which interfaces between grains were treated (sliding vs. non-sliding) was found to influence both mechanical and thermal responses to loading. Plastic deformation, mechanical work, and grain/grain frictional effects led to modest increases of mean temperature and local hotspots with maximum temperature not higher than 800–850 K for loadings investigated. For all scenarios investig... read less USED (low confidence) H. N. Pishkenari, F. S. Yousefi, and A. Taghibakhshi, “Determination of surface properties and elastic constants of FCC metals: a comparison among different EAM potentials in thin film and bulk scale,” Materials Research Express. 2018. link Times cited: 22 Abstract: Three independent elastic constants C11, C12, and C44 were c… read moreAbstract: Three independent elastic constants C11, C12, and C44 were calculated and compared using available potentials of eight different metals with FCC crystal structure; Gold, Silver, Copper, Nickel, Platinum, Palladium, Aluminum and Lead. In order to calculate the elastic constants, the second derivative of the energy density of each system was calculated with respect to different directions of strains. Each set of the elastic constants of the metals in bulk scale was compared with experimental results, and the average relative error was for each was calculated and compared with other available potentials. Then, using the Voigt-Reuss-Hill method, approximated values for Young and shear moduli and Poisson’s ratio of the FCC metals in the bulk scale were found for each potential. Furthermore, to observe the surface effects on the metals in nanoscale, surface elastic constants of the thin films of the metals have been calculated. In the study of the thin films of materials in nanoscale, the number of surface atoms is considerable compared to all atoms of the object. This leads to an increase in the surface effects, which influence the elastic properties. By considering this fact and employing related definitions and equations, the properties of the thin films of the metals were calculated, and the surface effects for different crystallographic directions were compared. Subsequently, in some cases, comparisons among characteristics of the metals in the thin film and bulk material were made. read less USED (low confidence) A. Kromik, E. Levchenko, C. Massobrio, and A. Evteev, “Diffusion in Ni–Zr Melts: Insights from Statistical Mechanics and Atomistic Modeling,” Advanced Theory and Simulations. 2018. link Times cited: 3 Abstract: An accurate database of diffusion properties of Ni–Zr melts … read moreAbstract: An accurate database of diffusion properties of Ni–Zr melts is generated within the framework of the molecular‐dynamics method in conjunction with a semi‐empirical many‐body interatomic potential. The reliability of the model description of Ni–Zr melts is confirmed via comparison of the simulation results with the existing experimental data on diffusion properties of Ni–Zr melts. A statistical mechanical formalism is employed to understand the behavior of the cross‐correlation between the interdiffusion flux and the force caused by the difference in the average random accelerations of atoms of different species in the short time limit t→0 . This theoretical description is exploited to analyze the simulation data on the diffusion properties of Ni–Zr melts. On this basis, it is found that in the composition range 0.25<∼xc Ni <∼x0.5 both single‐particle and collective diffusion dynamics slow down homogeneously upon undercooling of Ni–Zr melts. Furthermore, it is inferred that such homogeneous dynamical slowdown is related to the enhanced stability of undercooled melt against crystallization. As a consequence, Ni–Zr alloys within this composition range are identified as viable glass formers. read less USED (low confidence) Y. Shibuta, M. Ohno, and T. Takaki, “Advent of Cross‐Scale Modeling: High‐Performance Computing of Solidification and Grain Growth,” Advanced Theory and Simulations. 2018. link Times cited: 30 Abstract: The application range of computational metallurgy is rapidly… read moreAbstract: The application range of computational metallurgy is rapidly expanding thanks to the recent progress in high‐performance computing. In this Progress Report, state‐of‐the‐art collections of large‐scale simulations of solidification and grain growth, performed on the GPU supercomputer, are introduced. One of the notable achievements in this direction is a billion‐atom molecular dynamics simulation for nucleation and solidification, which revealed the heterogeneity in homogeneous nucleation. Moreover, a series of large‐scale phase‐field simulations shed light on the topics at issue including competitive growth of dendrites during the directional solidification, the effect of forced and natural convections on the solidification, and so on. Based on simulation results bridging the gap between atomistic and continuum‐based simulations, a new criterion of multi‐scale modeling is proposed in the age to come. We are now standing at the new era of cross‐scale modeling, in which the overlap between atomistic and continuum simulations creates new research concepts and fields. read less USED (low confidence) H. Peng, L. K. Huang, and F. Liu, “A thermo-kinetic correlation for grain growth in nanocrystalline alloys,” Materials Letters. 2018. link Times cited: 24 USED (low confidence) K. Choudhary, A. Biacchi, S. Ghosh, L. Hale, A. Walker, and F. Tavazza, “High-throughput assessment of vacancy formation and surface energies of materials using classical force-fields,” Journal of Physics: Condensed Matter. 2018. link Times cited: 16 Abstract: In this work, we present an open access database for surface… read moreAbstract: In this work, we present an open access database for surface and vacancy-formation energies using classical force-fields (FFs). These quantities are essential in understanding diffusion behavior, nanoparticle formation and catalytic activities. FFs are often designed for a specific application, hence, this database allows the user to understand whether a FF is suitable for investigating particular defect and surface-related material properties. The FF results are compared to density functional theory and experimental data whenever applicable for validation. At present, we have 17 506 surface energies and 1000 vacancy formation energies calculation in our database and the database is still growing. All the data generated, and the computational tools used, are shared publicly at the following websites: www.ctcms.nist.gov/~knc6/periodic.html, https://jarvis.nist.gov and https://github.com/usnistgov/jarvis. Approximations used during the high-throughput calculations are clearly mentioned. Using some of the example cases, we show how our data can be used to directly compare different FFs for a material and to interpret experimental findings such as using Wulff construction for predicting equilibrium shape of nanoparticles. Similarly, the vacancy formation energies data can be useful in understanding diffusion related properties. read less USED (low confidence) H.-ming Wu, C. Wu, N. Zhang, X.-nong Zhu, X. Ma, and L. Zhigilei, “Experimental and computational study of the effect of 1 atm background gas on nanoparticle generation in femtosecond laser ablation of metals,” Applied Surface Science. 2018. link Times cited: 19 USED (low confidence) G. Jung, W. C. Jeon, S. Lee, S.-H. Jung, S. Cho, and S. Kwak, “Reaction characteristics of Ni–Al nanolayers by molecular dynamics simulation,” Journal of Industrial and Engineering Chemistry. 2018. link Times cited: 8 USED (low confidence) E. Levchenko and A. Evteev, “Insight into interrelation between single-particle and collective diffusion in binary melts,” Physica A-statistical Mechanics and Its Applications. 2018. link Times cited: 4 USED (low confidence) C.-Y. Shih, C. Wu, H.-ming Wu, M. Shugaev, and L. Zhigilei, “Atomistic Simulations of the Generation of Nanoparticles in Short-Pulse Laser Ablation of Metals: Effect of Background Gas and Liquid Environments.” 2018. link Times cited: 1 Abstract: in the investigation of the fundamental mechanisms of laserm… read moreAbstract: in the investigation of the fundamental mechanisms of lasermaterial interactions. The advancements in the computational methodology and fast growth of available computing resources are rapidly expanding the range of problems amenable to atomistic modeling. This chapter provides an overview of the results obtained in recent simulations of laser ablation of metal targets in vacuum, a background gas, and a liquid environment. A comparison of the Chapter 12 read less USED (low confidence) L. Lin, S. Hui, G. Lu, S. Wang, X.-dong Wang, and D.-J. Lee, “Molecular dynamics study of high temperature wetting kinetics for Al/NiAl and Al/Ni3Al systems: Effects of grain boundaries,” Chemical Engineering Science. 2017. link Times cited: 12 USED (low confidence) P. Ji, Y. Rong, Y. Zhang, and Y. Tang, “Molecular Dynamics Investigation of Phase Change Induced by Ultrafast Laser Irradiation.” 2017. link Times cited: 0 USED (low confidence) G. Lu, L. Lin, S. Hui, S. Wang, X.-dong Wang, and D.-J. Lee, “Dewetting kinetics of metallic liquid films: Competition between unbalanced Young’s force and dissolutive reaction,” Chemical Physics Letters. 2017. link Times cited: 7 USED (low confidence) A. Hassani, A. Makan, K. Sbiaai, A. Tabyaoui, and A. Hasnaoui, “Incidence energy effect and impact assessment during homoepitaxial growth of nickel on (001), (111) and (110) surfaces,” Thin Solid Films. 2017. link Times cited: 21 USED (low confidence) Y. Gao and Z. Jin, “Interactions between lattice dislocation and Lomer-type low-angle grain boundary in nickel,” Computational Materials Science. 2017. link Times cited: 13 USED (low confidence) T. Ahmed et al., “Molecular Dynamics Prediction of the Influence of Composition on Thermotransport in Ni-Al Melts,” Diffusion Foundations. 2017. link Times cited: 5 Abstract: The influence of composition on thermotransport (coupling be… read moreAbstract: The influence of composition on thermotransport (coupling between mass and heat transport) in Ni-Al melts is investigated by making use of equilibrium molecular dynamics simulations in conjunction with the Green-Kubo formalism. To describe interatomic interactions in Ni-Al melt models, we employ the embedded-atom method potential developed in [G.P. Purja Pun, Y. Mishin, Phil. Mag., 2009, 89, 3245]. It is demonstrated that the employed interatomic potential gives good agreement with the recent experimental study [E. Sondermann, F. Kargl, A. Meyer, Presented at the 12th International Conference on Diffusion in Solids and Liquids (DSL-2016), 26-30 June 2016, Split, Croatia] regarding the direction of thermotransport in Al-rich liquid Ni-Al alloys. Moreover, the predicted values of the reduced heat of transport (the quantity which explicitly characterizes both the magnitude and direction of thermotransport) in Ni-Al melts, reveal fairly weak composition dependence while being practically independent of temperature at all. Accordingly, in the presence of a temperature gradient, our simulation results for the models of liquid Ni25Al75, Ni50Al50 and Ni75Al25 alloys predict consistently Ni and Al to migrate to the cold and hot ends, respectively. Meanwhile, the highest value, about eV, of the reduced heat of transport is observed for Ni50Al50 alloy model and it slightly decreases towards Al-rich and Ni-rich compositions. read less USED (low confidence) H. Wu et al., “A high-throughput methodology search for the optimum cooling rate in an advanced polycrystalline nickel base superalloy,” Materials & Design. 2017. link Times cited: 26 USED (low confidence) J. Ding, M. Asta, and R. Ritchie, “On the question of fractal packing structure in metallic glasses,” Proceedings of the National Academy of Sciences. 2017. link Times cited: 29 Abstract: Significance Our work clearly demonstrates a lack of fractal… read moreAbstract: Significance Our work clearly demonstrates a lack of fractal structure in metallic glasses, considering the packing of all atoms or solute-centered clusters. This finding clarifies the long-standing debate over the packing structure of metallic glasses from the perspective of fractal models; it is thus of significance for the community of researchers working with amorphous solids. Moreover, our percolation analysis of metallic glasses, revealing their cluster structure and percolation threshold, provides an important and powerful theoretical framework to describe the properties of amorphous alloys, such as the glass transition and mechanical deformation. This work addresses the long-standing debate over fractal models of packing structure in metallic glasses (MGs). Through detailed fractal and percolation analyses of MG structures, derived from simulations spanning a range of compositions and quenching rates, we conclude that there is no fractal atomic-level structure associated with the packing of all atoms or solute-centered clusters. The results are in contradiction with conclusions derived from previous studies based on analyses of shifts in radial distribution function and structure factor peaks associated with volume changes induced by pressure and compositional variations. The interpretation of such shifts is shown to be challenged by the heterogeneous nature of MG structure and deformation at the atomic scale. Moreover, our analysis in the present work illustrates clearly the percolation theory applied to MGs, for example, the percolation threshold and characteristics of percolation clusters formed by subsets of atoms, which can have important consequences for structure–property relationships in these amorphous materials. read less USED (low confidence) Q. Zhou, J. Wang, A. Misra, P. Huang, F. Wang, and K. Xu, “Dislocations interaction induced structural instability in intermetallic Al2Cu,” npj Computational Materials. 2017. link Times cited: 18 USED (low confidence) V. Turlo, O. Politano, and F. Baras, “Microstructure evolution and self-propagating reactions in Ni-Al nanofoils: An atomic-scale description,” Journal of Alloys and Compounds. 2017. link Times cited: 16 USED (low confidence) L. Lin, S. Hui, G. Lu, S. Wang, X.-dong Wang, and D.-J. Lee, “Molecular dynamics simulations on dissolutive wetting of Al–Ni alloy droplets on NiAl substrate,” Journal of The Taiwan Institute of Chemical Engineers. 2017. link Times cited: 13 USED (low confidence) R. Ramakrishnan and R. Sankarasubramanian, “Crystal-melt kinetic coefficients of Ni3Al,” Acta Materialia. 2017. link Times cited: 18 USED (low confidence) M. Chamani, G. Farrahi, and M. Movahhedy, “Friction behavior of nanocrystalline nickel near the Hall-Petch breakdown,” Tribology International. 2017. link Times cited: 17 USED (low confidence) R. Dikken, B. Thijsse, and L. Nicola, “Impingement of edge dislocations on atomically rough contacts,” Computational Materials Science. 2017. link Times cited: 5 USED (low confidence) J. J. Tang et al., “Microstructural design and oxidation resistance of CoNiCrAlY alloy coatings in thermal barrier coating system,” Journal of Alloys and Compounds. 2016. link Times cited: 34 USED (low confidence) V. Turlo, O. Politano, and F. Baras, “Modeling self-sustaining waves of exothermic dissolution in nanometric Ni-Al multilayers,” Acta Materialia. 2016. link Times cited: 27 USED (low confidence) X. Sedao et al., “Growth Twinning and Generation of High-Frequency Surface Nanostructures in Ultrafast Laser-Induced Transient Melting and Resolidification.,” ACS nano. 2016. link Times cited: 76 Abstract: The structural changes generated in surface regions of singl… read moreAbstract: The structural changes generated in surface regions of single crystal Ni targets by femtosecond laser irradiation are investigated experimentally and computationally for laser fluences that, in the multipulse irradiation regime, produce sub-100 nm high spatial frequency surface structures. Detailed experimental characterization of the irradiated targets combining electron back scattered diffraction analysis with high-resolution transmission electron microscopy reveals the presence of multiple nanoscale twinned domains in the irradiated surface regions of single crystal targets with (111) surface orientation. Atomistic- and continuum-level simulations performed for experimental irradiation conditions reproduce the generation of twinned domains and establish the conditions leading to the formation of growth twin boundaries in the course of the fast transient melting and epitaxial regrowth of the surface regions of the irradiated targets. The observation of growth twins in the irradiated Ni(111) targets provides strong evidence of the role of surface melting and resolidification in the formation of high spatial frequency surface structures. This also suggests that the formation of twinned domains can be used as a sensitive measure of the levels of liquid undercooling achieved in short pulse laser processing of metals. read less USED (low confidence) S. M. Rassoulinejad-Mousavi, Y. Mao, and Y. Zhang, “Evaluation of Copper, Aluminum and Nickel Interatomic Potentials on Predicting the Elastic Properties,” arXiv: Computational Physics. 2016. link Times cited: 63 Abstract: Choice of appropriate force field is one of the main concern… read moreAbstract: Choice of appropriate force field is one of the main concerns of any atomistic simulation that needs to be seriously considered in order to yield reliable results. Since, investigations on mechanical behavior of materials at micro/nanoscale has been becoming much more widespread, it is necessary to determine an adequate potential which accurately models the interaction of the atoms for desired applications. In this framework, reliability of multiple embedded atom method based interatomic potentials for predicting the elastic properties was investigated. Assessments were carried out for different copper, aluminum and nickel interatomic potentials at room temperature which is considered as the most applicable case. Examined force fields for the three species were taken from online repositories of National Institute of Standards and Technology (NIST), as well as the Sandia National Laboratories, the LAMMPS database. Using molecular dynamic simulations, the three independent elastic constants, C11, C12 and C44 were found for Cu, Al and Ni cubic single crystals. Voigt-Reuss-Hill approximation was then implemented to convert elastic constants of the single crystals into isotropic polycrystalline elastic moduli including Bulk, Shear and Young's modulus as well as Poisson's ratio. Simulation results from massive molecular dynamic were compared with available experimental data in the literature to justify the robustness of each potential for each species. Eventually, accurate interatomic potentials have been recommended for finding each of the elastic properties of the pure species. Exactitude of the elastic properties was found to be sensitive to the choice of the force fields. Those potentials were fitted for a specific compound may not necessarily work accurately for all the existing pure species. read less USED (low confidence) K. Xiong, H. Lu, and J. Gu, “Atomistic simulations of the nanoindentation-induced incipient plasticity in Ni3Al crystal,” Computational Materials Science. 2016. link Times cited: 38 USED (low confidence) M. Cherukara, T. Germann, E. Kober, and A. Strachan, “Shock Loading of Granular Ni/Al Composites. Part 2: Shock-Induced Chemistry,” Journal of Physical Chemistry C. 2016. link Times cited: 27 Abstract: We use molecular dynamics simulations to characterize the ch… read moreAbstract: We use molecular dynamics simulations to characterize the chemical processes resulting from the shock compaction of a loosely packed granular reactive composite of Ni and Al. For all of the impact strengths studied (with piston velocities up in the range 0.5–2.5 km/s), we find that reactions initiate in the vicinity of the collapsed pores. For the lowest impact velocities (up ≤ 0.75 km/s), the reactions that initiate at the collapsed pores subsequently slow down as thermal transport dissipates the initial temperature excursion and outpaces the exothermic energy release rate. At intermediate impact velocities (up ≈ 1.0 km/s), the localization of thermal kinetic energy is sufficient to establish a reaction rate that is self-sustaining in exothermic energy release, and the sample reacts within a few nanoseconds. At the highest impact velocities (up ≥ 1.5 km/s), the localization of translational kinetic energy as well as thermal energy following pore collapse drives the rapid propagation of the reaction from ... read less USED (low confidence) F. Baras, V. Turlo, and O. Politano, “Dissolution at Interfaces in Layered Solid-Liquid Thin Films: A Key Step in Joining Process,” Journal of Materials Engineering and Performance. 2016. link Times cited: 4 USED (low confidence) A. Mayer and P. N. Mayer, “Weak increase of the dynamic tensile strength of aluminum melt at the insertion of refractory inclusions,” Computational Materials Science. 2016. link Times cited: 9 USED (low confidence) J. Dziedzic, S. Winczewski, and J. Rybicki, “Structure and properties of liquid Al–Cu alloys: empirical potentials compared,” Computational Materials Science. 2016. link Times cited: 17 USED (low confidence) M. Chamani, G. Farrahi, and M. Movahhedy, “Molecular dynamics simulation of nanoindentation of nanocrystalline Al/Ni multilayers,” Computational Materials Science. 2016. link Times cited: 23 USED (low confidence) Y. Xia, C. Li, Y. Luan, X. J. Han, and J. Li, “Molecular dynamics studies on the correlation of undercoolability and thermophysical properties of liquid Ni–Al alloys,” Computational Materials Science. 2016. link Times cited: 7 USED (low confidence) B.-H. Wu, J. Zhou, C. Xue, and H. Liu, “Molecular dynamics simulation of the deposition and annealing of NiAl film on Ni substrate,” Applied Surface Science. 2015. link Times cited: 32 USED (low confidence) J. Huang, Z. Wang, Y. Luo, Y. Li, E. Yang, and Y. Chen, “Computational investigation of superalloy persistent slip bands formation,” 2015 21st International Conference on Automation and Computing (ICAC). 2015. link Times cited: 2 Abstract: Persistent slip bands (PSB) is the important and typical mic… read moreAbstract: Persistent slip bands (PSB) is the important and typical microstructure generated during fatigue crack initiation. Intensive works have been done to investigate the mechanisms of the formation of persistent slip bands in the past decade. In this paper, a molecular dynamics (MD) simulation associated with embedded atom model (EAM) is applied on the PSBs formation in nickel-base superalloys with different microstructure and temperature under tensile-tensile loadings. Simulation results show that PSBs formed within the γ phase by massive dislocations pile-up and propagation which can penetrate the grain. Also, the temperature will affect the material fatigue performance and blur PSBs appearance. The simulation results are in strong agreement with the experimental test results published before. read less USED (low confidence) V. Turlo, O. Politano, and F. Baras, “Dissolution process at solid/liquid interface in nanometric metallic multilayers: Molecular dynamics simulations versus diffusion modeling,” Acta Materialia. 2015. link Times cited: 40 USED (low confidence) D. Z. Chen et al., “Fractal atomic-level percolation in metallic glasses,” Science. 2015. link Times cited: 103 Abstract: Percolating cluster, factal structure Metallic glasses are a… read moreAbstract: Percolating cluster, factal structure Metallic glasses are appealing materials because they are strong and can bend without breaking. These materials are disordered but possess none of the defects seen in crystalline counterparts. Chen et al. developed a model for metallic glasses in which clusters of atoms float free in the liquid, begin to jam, and finally organize into a short-range fractal structure below the glass transition temperature. This model also accounted for the density and high strength characteristics of bulk samples. Science, this issue p. 1306 X-ray diffraction experiments and simulations show a crossover from fractal to homogeneous structure in metallic glasses. Metallic glasses are metallic alloys that exhibit exotic material properties. They may have fractal structures at the atomic level, but a physical mechanism for their organization without ordering has not been identified. We demonstrated a crossover between fractal short-range (<2 atomic diameters) and homogeneous long-range structures using in situ x-ray diffraction, tomography, and molecular dynamics simulations. A specific class of fractal, the percolation cluster, explains the structural details for several metallic-glass compositions. We postulate that atoms percolate in the liquid phase and that the percolating cluster becomes rigid at the glass transition temperature. read less USED (low confidence) A. Hassani, A. Makan, K. Sbiaai, A. Tabyaoui, and A. Hasnaoui, “Molecular dynamics study of growth and interface structure during aluminum deposition on Ni(1 0 0) substrate,” Applied Surface Science. 2015. link Times cited: 29 USED (low confidence) M. Cherukara, T. Weihs, and A. Strachan, “Molecular dynamics simulations of the reaction mechanism in Ni/Al reactive intermetallics,” Acta Materialia. 2015. link Times cited: 35 USED (low confidence) S. Kalidindi, J. A. Gomberg, Z. Trautt, and C. Becker, “Application of data science tools to quantify and distinguish between structures and models in molecular dynamics datasets,” Nanotechnology. 2015. link Times cited: 39 Abstract: Structure quantification is key to successful mining and ext… read moreAbstract: Structure quantification is key to successful mining and extraction of core materials knowledge from both multiscale simulations as well as multiscale experiments. The main challenge stems from the need to transform the inherently high dimensional representations demanded by the rich hierarchical material structure into useful, high value, low dimensional representations. In this paper, we develop and demonstrate the merits of a data-driven approach for addressing this challenge at the atomic scale. The approach presented here is built on prior successes demonstrated for mesoscale representations of material internal structure, and involves three main steps: (i) digital representation of the material structure, (ii) extraction of a comprehensive set of structure measures using the framework of n-point spatial correlations, and (iii) identification of data-driven low dimensional measures using principal component analyses. These novel protocols, applied on an ensemble of structure datasets output from molecular dynamics (MD) simulations, have successfully classified the datasets based on several model input parameters such as the interatomic potential and the temperature used in the MD simulations. read less USED (low confidence) S. Wilson, K. Gunawardana, and M. Mendelev, “Solid-liquid interface free energies of pure bcc metals and B2 phases.,” The Journal of chemical physics. 2015. link Times cited: 32 Abstract: The solid-liquid interface (SLI) free energy was determined … read moreAbstract: The solid-liquid interface (SLI) free energy was determined from molecular dynamics (MD) simulation for several body centered cubic (bcc) metals and B2 metallic compounds (space group: Pm3̄m; prototype: CsCl). In order to include a bcc metal with a low melting temperature in our study, a semi-empirical potential was developed for Na. Two additional synthetic "Na" potentials were also developed to explore the effect of liquid structure and latent heat on the SLI free energy. The obtained MD data were compared with the empirical Turnbull, Laird, and Ewing relations. All three relations are found to predict the general trend observed in the MD data for bcc metals obtained within the present study. However, only the Laird and Ewing relations are able to predict the trend obtained within the sequence of "Na" potentials. The Laird relation provides the best prediction for our MD data and other MD data for bcc metals taken from the literature. Overall, the Laird relation also agrees well with our B2 data but requires a proportionality constant that is substantially different from the bcc case. It also fails to explain a considerable difference between the SLI free energies of some B2 phases which have nearly the same melting temperature. In contrast, this difference is satisfactorily described by the Ewing relation. Moreover, the Ewing relation obtained from the bcc dataset also provides a reasonable description of the B2 data. read less USED (low confidence) D. Z. Chen, X. Gu, Q. An, W. Goddard, and J. Greer, “Ductility and work hardening in nano-sized metallic glasses,” Applied Physics Letters. 2015. link Times cited: 34 Abstract: In-situ nano-tensile experiments on 70 nm-diameter free-stan… read moreAbstract: In-situ nano-tensile experiments on 70 nm-diameter free-standing electroplated NiP metallic glass nanostructures reveal tensile true strains of ∼18%, an amount comparable to compositionally identical 100 nm-diameter focused ion beam samples and ∼3 times greater than 100 nm-diameter electroplated samples. Simultaneous in-situ observations and stress-strain data during post-elastic deformation reveal necking and work hardening, features uncharacteristic for metallic glasses. The evolution of free volume within molecular dynamics-simulated samples suggests a free surface-mediated relaxation mechanism in nano-sized metallic glasses. read less USED (low confidence) M. Cherukara, T. Germann, E. Kober, and A. Strachan, “Shock Loading of Granular Ni/Al Composites. Part 1. Mechanics of Loading,” Journal of Physical Chemistry C. 2014. link Times cited: 42 Abstract: We present molecular dynamics simulations of the thermomecha… read moreAbstract: We present molecular dynamics simulations of the thermomechanical response under shock loading of a granular material consisting of laminated Ni/Al grains. We observe two regimes: At low piston velocities (up ≲ 1km/s), the shock wave is diffuse, and the width of the shock front decreases with increasing piston velocity. Beyond a critical shock strength, however, the width remains relatively constant at approximately the mean grain radius. This change in behavior follows from an evolution of the mechanism of compaction with increasing insult strength. Furthermore, the mechanism evolves from plastic deformation-mediated pore collapse for relatively weak shocks, to solid extrusion and fluid ejecta filling pores ahead of the shock front at intermediate strengths, and finally to atomic jetting into the pore for very strong shocks (up ≳ 2 km/s). High-energy fluid ejecta into pores leads to the formation of flow vorticity and can result in a large fraction of the input energy localizing into translational kinetic energy components including the formation of hot spots. This has implications for the mechanical mixing of Ni and Al in these reactive composites. read less USED (low confidence) P. Schelling, J. Ernotte, L. Shokeen, J. W. Halley, and W. Tucker, “Molecular-dynamics calculation of the vacancy heat of transport,” Journal of Applied Physics. 2014. link Times cited: 2 Abstract: We apply the recently developed constrained-dynamics method … read moreAbstract: We apply the recently developed constrained-dynamics method to elucidate the thermodiffusion of vacancies in a single-component material. The derivation and assumptions used in the method are clearly explained. Next, the method is applied to compute the reduced heat of transport Qv*−hfv for vacancies in a single-component material. Results from simulations using three different Morse potentials, with one providing an approximate description of Au, and an embedded-atom model potential for Ni are presented. It is found that the reduced heat of transport Qv*−hfv may take either positive or negative values depending on the potential parameters and exhibits some dependence on temperature. It is also found that Qv*−hfv may be correlated with the activation entropy. The results are discussed in comparison with experimental and previous simulation results. read less USED (low confidence) H. Sun and C. Deng, “Adapted solute drag model for impurity-controlled grain boundary motion,” Journal of Materials Research. 2014. link Times cited: 10 Abstract: In this study, impurity segregation and solute drag effects … read moreAbstract: In this study, impurity segregation and solute drag effects on grain boundary (GB) motion were investigated in a binary Al-Ni model system with an inclined Σ5 GB by direct molecular dynamics simulations. By extending the interface random walk method to impure systems, it was found that the GB mobility was significantly influenced by the segregated impurities, which generally decreased as the impurity concentration increased. Moreover, based on simulations at different temperatures and impurity concentrations, we validated that the solute drag effects can be well modeled by the theory proposed by Cahn, Lücke, and Stüwe (CLS model) more than 50 years ago, provided that proper adaptations were made. In particular, we found that in strongly segregated GB system, the boundary mobility was deeply correlated to the impurity diffusivity in the direction perpendicular to the boundary plane in the frame of the moving boundary, instead of the impurity bulk diffusivity assumed in the original CLS model and many past studies. read less USED (low confidence) C.-B. Wang, W. Zhang, C. Ren, P. Huai, and Z. Zhu, “The effect of temperature on primary defect formation in Ni–Fe alloy,” Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms. 2014. link Times cited: 16 USED (low confidence) H.-Z. Wu and S. Zhao, “Reaction pathway of Ni/Al clad particles under thermal loading: A molecular dynamics simulation,” Journal of Alloys and Compounds. 2013. link Times cited: 15 USED (low confidence) R. Babicheva, K. A. Bukreeva, S. Dmitriev, R. Mulyukov, and K. Zhou, “Strengthening of NiAl nanofilms by introducing internal stresses,” Intermetallics. 2013. link Times cited: 13 USED (low confidence) A. Ovrutsky and A. Prokhoda, “Particularities of nucleation and growth of the B2-phase: Results of simulations for the Al50Ni50 alloy,” Computational Materials Science. 2013. link Times cited: 6 USED (low confidence) R. Babicheva, K. A. Bukreeva, S. Dmitriev, and K. Zhou, “Discontinuous elastic strain observed during stretching of NiAl single crystal nanofilms,” Computational Materials Science. 2013. link Times cited: 9 USED (low confidence) D. Z. Chen, D. Jang, K. Guan, Q. An, W. A. Goddard, and J. R. Greer, “Nanometallic glasses: size reduction brings ductility, surface state drives its extent.,” Nano letters. 2013. link Times cited: 115 Abstract: We report tensile experiments on Ni80P20 metallic glass samp… read moreAbstract: We report tensile experiments on Ni80P20 metallic glass samples fabricated via a templated electroplating process and via focused ion beam milling, which differed only in their surface energy states: Ga-ion-irradiated and as-electroplated. Molecular dynamics simulations on similar Ni80Al20 systems corroborate the experimental results, which suggest that the transition from brittle to ductile behavior is driven by sample size, while the extent of ductility is driven by surface state. read less USED (low confidence) Y. Zhu, Z. Li, and M. Huang, “Atomistic modeling of the interaction between matrix dislocation and interfacial misfit dislocation networks in Ni-based single crystal superalloy,” Computational Materials Science. 2013. link Times cited: 62 USED (low confidence) K. Vishnu, M. Cherukara, H. Kim, and A. Strachan, “Amorphous Ni/Al nanoscale laminates as high-energy intermolecular reactive composites,” Physical Review B. 2012. link Times cited: 18 Abstract: We use molecular dynamics simulations to explore the potenti… read moreAbstract: We use molecular dynamics simulations to explore the potential use of amorphous metals in intermolecular reactive composites. Our simulations show that amorphous Ni/Al nanolaminates lead to an increase in temperature ofup to 260 K over their crystalline counterparts, this increase corresponds to over 20% of the heat of fusion and can be explained in terms of the amorphization energy. The reactions are diffusion controlled and crystallization is observed in laminates with relatively long periods where high temperatures are experienced for sufficiently long times prior to intermixing; the effect of this process on the energetics and time involved in the reaction are characterized. read less USED (low confidence) E. Levchenko, A. Evteev, G. Löwisch, I. Belova, and G. Murch, “Molecular dynamics simulation of alloying in a Ti-coated Al nanoparticle,” Intermetallics. 2012. link Times cited: 24 USED (low confidence) S. Rao, D. Dimiduk, T. Parthasarathy, M. Uchic, and C. Woodward, “Atomistic simulations of intersection cross-slip nucleation in L12 Ni3Al,” Scripta Materialia. 2012. link Times cited: 15 USED (low confidence) E. Glaessgen, E. Saether, S. W. Smith, J. Hochhalter, V. Yamakov, and V. Gupta, “Modeling and Characterization of Damage Processes in Metallic Materials.” 2011. link Times cited: 4 Abstract: This paper describes a broad effort that is aimed at underst… read moreAbstract: This paper describes a broad effort that is aimed at understanding the fundamental mechanisms of crack growth and using that understanding as a basis for designing materials and enabling predictions of fracture in materials and structures that have small characteristic dimensions. This area of research, herein referred to as Damage Science, emphasizes the length scale regimes of the nanoscale and the microscale for which analysis and characterization tools are being developed to predict the formation, propagation, and interaction of fundamental damage mechanisms. Examination of nanoscale processes requires atomistic and discrete dislocation plasticity simulations, while microscale processes can be examined using strain gradient plasticity, crystal plasticity and microstructure modeling methods. Concurrent and sequential multiscale modeling methods are being developed to analytically bridge between these length scales. Experimental methods for characterization and quantification of near-crack tip damage are also being developed. This paper focuses on several new methodologies in these areas and their application to understanding damage processes in polycrystalline metals. On-going and potential applications are also discussed. read less USED (low confidence) A. Nikonov, A. Dmitriev, and A. Smolin, “Selection of the potential for MD-modeling of phase martensitic transformations in Al-Cu-Ni alloy,” PROCEEDINGS OF THE INTERNATIONAL CONFERENCE “PHYSICAL MESOMECHANICS. MATERIALS WITH MULTILEVEL HIERARCHICAL STRUCTURE AND INTELLIGENT MANUFACTURING TECHNOLOGY.” 2022. link Times cited: 1 USED (low confidence) A. Khoei, M. Youzi, and G. T. Eshlaghi, “Mechanical Properties And γ/γ’ Interfacial Misfit Network Evolution: A Study Towards the Creep Behavior of Ni-Based Single Crystal Superalloys,” MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic). 2021. link Times cited: 0 Abstract: The aim of this study is to investigate the role of the temp… read moreAbstract: The aim of this study is to investigate the role of the temperature, stress, strain rate, and rhenium (Re) on the γ/γ' interfacial misfit dislocation network and mechanical response of Ni-based single crystal superalloys. Due to the mismatch between the two phases, a dislocation network forms after aging at high temperatures to alleviate the stress field. The (100), (110), and (111) phase interface models are generated to further study the properties of the superalloy by applying molecular dynamics simulations. It is noted that the strength and stability of the network are diminished as the thermal condition intensifies owing to the dispersed atomic potential energy at the interface. By applying a constant strain rate of 2x108 (s-1) at 0 K, the (100) and (111) phase interface models lose the co-coordinating role of maintaining the dynamic equilibrium. Hence, dislocations pile-up in the damaged area, and the network is no longer able to fortify the interface. For the (110) phase interface model, the dominant deformational mechanism is precipitate shearing. As temperature increases, the elastic modulus, initial mismatch stress, and yield strength decrease. Moreover, the yield strength of material increases as the strain rate increases. The pinning effect of Re atoms is surveyed by replacing 3.293at%, and 5at% of matrix Ni atoms with Re at 1600 K. The dislocation hampering property of Re is more perceptible when enough dislocations in the γ phase are moving at elevated temperatures. In addition, Re manages to soothe the stress field at the interface and does not affect the network morphology. Finally, an investigation of the creep behavior of the superalloy is provided. It is observed that the escalated damage to the interfacial network due to the increased temperature leads to the domination of the softening mechanisms (cross-slip and dislocation climb) on the deformation and shortens the steady-state creep. Moreover, Re atoms act as an extra hardening factor to improve the tertiary creep. read less USED (low confidence) A. Kromik, E. Levchenko, and A. Evteev, “Diffusion Kinetics in Binary Liquid Alloys with Ordering and Demixing Tendencies.” 2020. link Times cited: 0 USED (low confidence) J. Tang et al., “Activation volume dominated diffusivity of Ni50Al50 melt under extreme conditions,” Computational Materials Science. 2020. link Times cited: 6 USED (low confidence) A. G. Pourkermani, B. Azizi, and H. N. Pishkenari, “Vibrational analysis of Ag, Cu and Ni nanobeams using a hybrid continuum-atomistic model,” International Journal of Mechanical Sciences. 2020. link Times cited: 9 USED (low confidence) V. Jordan and I. Shmakov, “Thermal and Microstructural Analysis of Intermetallide Synthesis in the Ni-Al Layered-Block Atomic Structure Based on the Computer-Aided Simulation of SHS.” 2020. link Times cited: 1 USED (low confidence) W. Nöhring, “Dislocation Cross-Slip in Face-Centered Cubic Solid Solution Alloys.” 2018. link Times cited: 2 Abstract: The mechanical strength of metals depends on their resistanc… read moreAbstract: The mechanical strength of metals depends on their resistance against various microscopic deformation processes. In ductile metals, the most important process is shearing of the crystal lattice by dislocations. One of the fundamental aspects of dislocation motion is cross-slip of screw dislocations, the process by which they change their glide plane. In Face-Centered Cubic (FCC) metals, cross-slip is supposed to play a role in dislocation structuring, work hardening, recovery, fatigue, etc. Most prior studies on cross-slip in FCC metals focused on pure metals. There have been few studies of solute effects on cross-slip, which are important for engineering alloys. Here, the effects of substitutional solutes are studied using atomistic simulations and statistical modeling. In the first part of the thesis, the mechanism and energy of cross-slip of short (40 Burgers vectors long) dislocations in Ni-Al, Al-Mg and Cu-Ni alloys are determined using atomistic calculations. These calculations are carried out with real random alloys and with “average” alloys, where the real atom types are replaced by a single average type. By comparison, it is shown that cross-slip is controlled by fluctuations in the solute concentration, i.e. the activation energy for cross-slip is a distributed variable with a large variance around the mean value. The latter changes only little with concentration. Most importantly, activation energies that are significantly lower than the mean value can be observed in random alloys. A linear correlation between the activation energy and the energy difference between the state of the dislocation before and after cross-slip is observed. An analytical, parameter-free model of this energy difference is developed, which takes random changes in solute-dislocation and solute-solute binding energies into account. Thus, it is possible to predict the distribution of activation energies for nucleation of cross-slip. In the second part, cross-slip of long (102–103 Burgers vectors) dislocations is studied using a random walk model. Cross-slip is seen as a discrete process, where one Burgers vector long subsegments of the dislocation cross-slip one after another. Associated with each step is a random energy due to random changes in solute binding energies, as well as a deterministic energy change due to constriction formation and stress effects. The random walk model allows the calculation of the activation energy distribution for arbitrary dislocation lengths and stresses. Cross-slip of long dislocations is unlikely at zero stress, due to increasing frequency of high activation energies with increasing length. However, an external stress eliminates these high barriers. Cross-slip then becomes a weakest-link problem. Like in the case of short dislocations, activation energies that are significantly lower than average-alloy estimates can be observed in real random alloys. read less USED (low confidence) H. Zheng, B. Li, Y. Tan, G. Li, X. Shu, and P. Peng, “Derivative effect of laser cladding on interface stability of YSZ@Ni coating on GH4169 alloy: An experimental and theoretical study,” Applied Surface Science. 2018. link Times cited: 8 USED (low confidence) E. Karchevskaya, D. Minakov, and P. Levashov, “Quantum molecular dynamics simulation of structural and thermodynamic properties of NiAl,” Journal of Physics: Conference Series. 2018. link Times cited: 0 Abstract: In this work, structural and thermodynamic properties of a s… read moreAbstract: In this work, structural and thermodynamic properties of a solid and liquid Ni–Al compound are studied using an ab initio method of quantum molecular dynamics (QMD). Simulations were carried out in 700–3000 K temperature range at atmospheric pressure. Radial distribution functions are analyzed to determine the presence of Ni–Al chemical bonds. Diffusion coefficients for individual components are also calculated. Another goal of this work is the investigation of the reaction propagation in thermally-initiated Ni–Al foils. For this purpose, we performed QMD simulations of Ni–Al layers in the microcanonical ensemble. An exothermic reaction between the solid Ni–Al layers is observed in our simulations at temperature less than the melting temperatures of the components. read less USED (low confidence) J. Kristensen, I. Bilionis, and N. Zabaras, “Adaptive Simulation Selection for the Discovery of the Ground State Line of Binary Alloys with a Limited Computational Budget.” 2017. link Times cited: 11 USED (low confidence) Q.-N. Fan, C.-yu Wang, T. Yu, and J.-ping Du, “A ternary Ni–Al–W EAM potential for Ni-based single crystal superalloys,” Physica B-condensed Matter. 2015. link Times cited: 11 USED (low confidence) A. Ovrutsky, A. Prokhoda, and M. Rasshchupkyna, “Modern Simulations by the Molecular Dynamics Method.” 2014. link Times cited: 0 USED (low confidence) C. Wu and L. Zhigilei, “Microscopic mechanisms of laser spallation and ablation of metal targets from large-scale molecular dynamics simulations,” Applied Physics A. 2014. link Times cited: 255 USED (low confidence) X. Lai, L. Liu, H. Mei, and P. Zhai, “Molecular dynamics study on the mechanical characteristics of Al-terminated Al/α-Al2O3 interface under tensile loading,” International Journal of Materials & Product Technology. 2011. link Times cited: 0 Abstract: Molecular dynamics simulation has been performed to study th… read moreAbstract: Molecular dynamics simulation has been performed to study the mechanical properties and behaviour of the interface between Al and Al- terminated α-Al2O3 under tension loading. The atomistic structures of the metal/ceramic interface are first modelled according to experimental results. The interatomic potential utilised here is a multicomponent potential proposed by us. The results reveal that atomic rearrangement caused by lattice misfit occurs after relaxation, expressed as the stacking-fault islands at the interface, which shows reasonable agreement with experiments. During the tension process, the system reaches its ultimate strength 7.89 GPa at strain 11.08% when the crack nucleation emerges in the aluminium. read less NOT USED (low confidence) A. Khoei, M. R. Seddighian, and A. R. Sameti, “Machine learning-based multiscale framework for mechanical behavior of nano-crystalline structures,” International Journal of Mechanical Sciences. 2023. link Times cited: 0 NOT USED (low confidence) S. Röcken and J. Zavadlav, “Accurate machine learning force fields via experimental and simulation data fusion,” ArXiv. 2023. link Times cited: 0 Abstract: Machine Learning (ML)-based force fields are attracting ever… read moreAbstract: Machine Learning (ML)-based force fields are attracting ever-increasing interest due to their capacity to span spatiotemporal scales of classical interatomic potentials at quantum-level accuracy. They can be trained based on high-fidelity simulations or experiments, the former being the common case. However, both approaches are impaired by scarce and erroneous data resulting in models that either do not agree with well-known experimental observations or are under-constrained and only reproduce some properties. Here we leverage both Density Functional Theory (DFT) calculations and experimentally measured mechanical properties and lattice parameters to train an ML potential of titanium. We demonstrate that the fused data learning strategy can concurrently satisfy all target objectives, thus resulting in a molecular model of higher accuracy compared to the models trained with a single data source. The inaccuracies of DFT functionals at target experimental properties were corrected, while the investigated off-target properties remained largely unperturbed. Our approach is applicable to any material and can serve as a general strategy to obtain highly accurate ML potentials. read less NOT USED (low confidence) Z. Ma and Z. Pan, “Efficient machine learning of solute segregation energy based on physics-informed features,” Scientific Reports. 2023. link Times cited: 0 NOT USED (low confidence) R. N. L. Terrett and T. Frankcombe, “Reactive Bimetallic Nanostructures Based on Triply Periodic Minimal Surfaces: A Molecular Dynamics Study toward the Limits of Performance.,” ACS applied materials & interfaces. 2023. link Times cited: 2 Abstract: A variety of intermetallic compounds possesses high enthalpi… read moreAbstract: A variety of intermetallic compounds possesses high enthalpies of formation. These compounds may be formed from reactive compacts or nanostructures comprised of unreacted precursor metals. These precursor structures support self-propagating high temperature synthesis (SHS) reactions which afford very high specific energy densities and rates, with excellent spatial control and a variety of useful applications. The present work compares the reactivity of notional bimetallic nanostructures based on well-known triply periodic minimal surfaces (TPMSes) with the popular reactive nanolaminate (RNL) modality for the Ni/Al system, using a molecular dynamics approach. TPMS-derived nanostructures were found to have lower ignition energies and faster reaction rates than RNLs of comparable periodicity, while the maximum achievable temperature of ignitions was found to be modulated by a complex interplay of factors including reaction rate and specific metal/metal interface density. Nanostructure reactivity and thermochemistry is also affected by effective diffusion dimensionality and recalescent precipitation of intermetallic crystallites. The TPMS-derived reactive nanostructures presented herein anticipate plausible advances in nanofabrication technology. read less NOT USED (low confidence) A. Khoei and M. Kianezhad, “A machine learning-based atomistic-continuum multiscale technique for modeling the mechanical behavior of Ni3Al,” International Journal of Mechanical Sciences. 2022. link Times cited: 12 NOT USED (low confidence) H. Chen 陈 et al., “Modification of short-range repulsive interactions in ReaxFF reactive force field for Fe–Ni–Al alloy,” Chinese Physics B. 2021. link Times cited: 1 Abstract: The short-range repulsive interactions of any force field mu… read moreAbstract: The short-range repulsive interactions of any force field must be modified to be applicable for high energy atomic collisions because of extremely far from equilibrium state when used in molecular dynamics (MD) simulations. In this work, the short-range repulsive interaction of a reactive force field (ReaxFF), describing Fe–Ni–Al alloy system, is well modified by adding a tabulated function form based on Ziegler–Biersack–Littmark (ZBL) potential. The modified interaction covers three ranges, including short range, smooth range, and primordial range. The short range is totally predominated by ZBL potential. The primordial range means the interactions in this range is the as-is ReaxFF with no changes. The smooth range links the short-range ZBL and primordial-range ReaxFF potentials with a taper function. Both energies and forces are guaranteed to be continuous, and qualified to the consistent requirement in LAMMPS. This modified force field is applicable for simulations of energetic particle bombardments and reproducing point defects' booming and recombination effectively. read less NOT USED (low confidence) Q. J. Li, E. Küçükbenli, S. T. Lam, B. Khaykovich, E. Kaxiras, and J. Li, “Development of robust neural-network interatomic potential for molten salt.” 2021. link Times cited: 38 NOT USED (low confidence) V. Jordan and I. Shmakov, “The influence of the ignition conditions of the SH-synthesis of intermetallic compounds on the combustion parameters of the Ti-15.82wt.%Al composition: computer simulation and computing experiments,” Journal of Physics: Conference Series. 2019. link Times cited: 0 Abstract: Computational experiments (CEs) have been carried out to sim… read moreAbstract: Computational experiments (CEs) have been carried out to simulate the propagation of the combustion wave of the SH-synthesis process in a package of alternating layers of nanoscale crystal lattices of Ti and Al atoms by molecular dynamics method. The interatomic interaction potential in the embedded atom model (EAM) was used in the LAMMPS package. Using the LAMMPS configuration with parallel computing, the following results of CEs were obtained: sets of temperature profiles along the layers of the structure at successive instants of time (up to 16 ns) and the corresponding sets of snapshots (vertical cross-sections of the atomic arrangement along the layers), as well as a tables with the number and percentage of the content of various types of elementary cells (fcc, hcp, bcc, other) at the same instants of time. The influence of the initiation’s conditions of the SH-synthesis of intermetallic compounds on the combustion parameters of the nanoscale layered Ti-15.82wt.%Al composition was showed. The ignition conditions of SHS that are provided the stable motion of the combustion wave in the SHS-sample were determined. And the ignition conditions of SHS with dominance of either TiAl or Ti3Al phase formation in the SHS products was also determined. read less NOT USED (low confidence) V. Jordan and I. Shmakov, “The emergence of a heterostructure of the intermetallic phases in the process of SH-synthesis simulation in a nonstoichiometric nanoscale layered Ti-Al system,” Journal of Physics: Conference Series. 2019. link Times cited: 1 Abstract: Computational experiments (CEs) have been carried out to sim… read moreAbstract: Computational experiments (CEs) have been carried out to simulate the propagation of the combustion wave of the SH-synthesis process in a package of alternating nanosized layers of crystal lattices of Ti and Al atoms by the «molecular dynamics» method. By means the LAMMPS package performing parallel computing the computational experiments (CEs) have been carried out. The “embedded atom” model (EAM) for the interatomic interaction potential was used. The two structures of Ti-Al system with various quantities of atoms and nonstoichiometric ratios have been studied. The sets of temperature and density profiles along the layered structure at successive instants of time (up to 16 ns) have been calculated. In addition, the corresponding sets of vertical cross-sections of the distributions of atoms and various types of elementary cells (fcc, hcp, bcc, etc.) have been calculated. The emergence of heterostructure of intermetallic phases in the Ti-Al system with 453974 atoms and the nonstoichiometric ratio of 1.23 has been detected. read less NOT USED (low confidence) V. Jordan and I. Shmakov, “Reproducibility of a heterophase structure emergence effect when changing the ignition temperature of SHS in a layered nanosized nonstoichiometric Ti-Al system,” Journal of Physics: Conference Series. 2019. link Times cited: 2 Abstract: The simulation results of SHS process in a package of altern… read moreAbstract: The simulation results of SHS process in a package of alternating nanoscale layers of the crystal lattices of Ti and Al atoms for two systems with various numbers of atoms and nonstoichiometric ratios are given. For simulation the LAMMPS package supporting parallel computations and the interatomic interaction potential in the “embedded atom” model (EAM) have been used. For two systems with various numbers of atoms and nonstoichiometric ratios the sets of temperature and density profiles along the layers of the structure at successive instants of time (up to 16 ns) have been obtained. For a system with 453974 atoms and a nonstoichiometric ratio of 1.23 the heterostructure emergence with an alternation of intermetallic phases when changing the SHS “ignition” temperature has been reproduced. read less NOT USED (low confidence) G. D. Smith, S. Bardenhagen, and J. Nairn, “Mesoscale modeling of Al/Ni composites,” International Journal of Impact Engineering. 2019. link Times cited: 3 NOT USED (low confidence) S. Reeve, A. Belessiotis-Richards, and A. Strachan, “Harnessing mechanical instabilities at the nanoscale to achieve ultra-low stiffness metals,” Nature Communications. 2017. link Times cited: 13 NOT USED (low confidence) Z.-L. Liu, R. Li, X.-L. Zhang, N. Qu, and L. Cai, “Direct anharmonic correction method by molecular dynamics,” Comput. Phys. Commun. 2017. link Times cited: 3 NOT USED (low confidence) Z. Trautt, F. Tavazza, and C. Becker, “Facilitating the selection and creation of accurate interatomic potentials with robust tools and characterization,” Modelling and Simulation in Materials Science and Engineering. 2015. link Times cited: 14 Abstract: The Materials Genome Initiative seeks to significantly decre… read moreAbstract: The Materials Genome Initiative seeks to significantly decrease the cost and time of development and integration of new materials. Within the domain of atomistic simulations, several roadblocks stand in the way of reaching this goal. While the NIST Interatomic Potentials Repository hosts numerous interatomic potentials (force fields), researchers cannot immediately determine the best choice(s) for their use case. Researchers developing new potentials, specifically those in restricted environments, lack a comprehensive portfolio of efficient tools capable of calculating and archiving the properties of their potentials. This paper elucidates one solution to these problems, which uses Python-based scripts that are suitable for rapid property evaluation and human knowledge transfer. Calculation results are visible on the repository website, which reduces the time required to select an interatomic potential for a specific use case. Furthermore, property evaluation scripts are being integrated with modern platforms to improve discoverability and access of materials property data. To demonstrate these scripts and features, we will discuss the automation of stacking fault energy calculations and their application to additional elements. While the calculation methodology was developed previously, we are using it here as a case study in simulation automation and property calculations. We demonstrate how the use of Python scripts allows for rapid calculation in a more easily managed way where the calculations can be modified, and the results presented in user-friendly and concise ways. Additionally, the methods can be incorporated into other efforts, such as openKIM. read less NOT USED (low confidence) A. B. Lidiard, “An Essay on the Heat of Transport in Solids and a Partial Guide to the Literature,” Diffusion Foundations. 2015. link Times cited: 4 Abstract: This article reviews the subject of the Soret effect and The… read moreAbstract: This article reviews the subject of the Soret effect and Thermodiffusion in solids more generally. In doing so it draws upon computer simulations made with a method (the Grout-Gillan method) derived from the Green-Kubo approach to transport coefficients in solids. The insights into the make-up of heats of transport parameters, Q*, so obtained are described and used to provide additional insight into measured heats of transport in situations where no reliable theories or simulations exist. These insights also point to the relations between heats of transport on the one hand and phonon thermal conductivity and focussed collision sequences on the other. These relations point to circumstances where the heat of transport may be small (e.g. low coordination in the lattice) or can be estimated from heats of activation for atom movements. In other cases the Grout-Gillan simulation method may offer the most reliable approach. These new insights are expected to be useful in materials modelling. read less NOT USED (low confidence) L. Alawieh, T. Weihs, and O. Knio, “A generalized reduced model of uniform and self-propagating reactions in reactive nanolaminates,” Combustion and Flame. 2013. link Times cited: 49 NOT USED (low confidence) E. Levchenko, Y. Dappe, and G. Ori, “Theory and Simulation in Physics for Materials Applications: Cutting-Edge Techniques in Theoretical and Computational Materials Science,” Theory and Simulation in Physics for Materials Applications. 2020. link Times cited: 3 NOT USED (low confidence) С. Волегов, Р. М. Герасимов, and Р. П. Давлятшин, “MODELS OF MOLECULAR DYNAMICS: A REVIEW OF EAM-POTENTIALS. PART 2. POTENTIALS FOR MULTI-COMPONENT SYSTEMS.” 2018. link Times cited: 1 Abstract: Получена: 18 мая 2018 г. Принята: 25 июня 2018 г. Опубликова… read moreAbstract: Получена: 18 мая 2018 г. Принята: 25 июня 2018 г. Опубликована: 29 июня 2018 г. В статье представлена вторая часть обзора современных подходов и работ, посвященных построению потенциалов межатомного взаимодействия с использованием методологии погруженного атома (EAM-потенциалы). Эта часть обзора посвящена одной из наиболее остро стоящих проблем в молекулярной динамике – вопросам построения потенциалов, которые были бы пригодны для описания структуры и физико-механических свойств многокомпонентных (в первую очередь – бинарных и тернарных) материалов. Отмечены первые работы, в которых предлагались подходы к построению функций перекрестного взаимодействия для сплавов никеля и меди – как с использованием методологии EAM, так и несколько отличающийся по процедуре построения потенциал типа Финисса-Синклера. Рассматриваются работы, в которых производится сопоставление различных подходов к построению потенциалов, а также к процедуре идентификации их параметров на примере одних и тех же многокомпонентных систем (типа Al-Ni или Cu-Au). Кроме того, особый интерес представляют некоторые тернарные системы, например Fe–Ni–Cr, W–H– He или U–Mo–Xe, которые являются ключевыми для материалов атомной энергетики и которые в последние годы активно изучаются как возможные материалы для использования в термоядерных ректорах. Приведены примеры работ, в которых предлагаются и исследуются потенциалы для описания многокомпонентных систем, пригодных для использования в аэрокосмической промышленности и изготовленных прежде всего на основе никеля. Рассмотрены результаты исследований различных интерметаллических соединений, отмечены работы, в которых при помощи построенного EAM потенциала удалось количественно точно описать фазовые диаграммы соединений и вычислить характеристики фазовых переходов. read less NOT USED (high confidence) H. Juárez et al., “Modeling of surface phenomena of liquid Al–Ni alloys using molecular dynamics,” Scientific Reports. 2023. link Times cited: 0 NOT USED (high confidence) I. Shmakov, “Extension of the functionality of the software for MD-simulation of the SH-synthesis of intermetallides in Ni-Al and Ti-Al nanosystems,” Yugra State University Bulletin. 2022. link Times cited: 0 Abstract: The subject of research: the methodological and functional c… read moreAbstract: The subject of research: the methodological and functional capabilities of specialized software packages of free access LAMMPS and OVITO and author's programs used for simulation of SHS-microkinetics in heterogeneous systems.
Purpose of research: to increase information content, 3D-visualization, and adequate interpretation of the processes of structural-phase transformations at interfaces of the layered, layered-block nanoscale Ni-Al and Ti-Al systems.
Methods and objects of redearch: the molecular dynamics simulation method implemented in the basis of the LAMMPS software package simulates the process of initiation and propagation of the SHS combustion wave in the systems under study, and using the OVITO package, 3D-visualization of the processes of dissolution, diffusion, and motion of the SHS combustion wave front is carried out.
Main results of research: it is shown that the development by the author of software modules for calculating one-dimensional temperature and density profiles of the synthesized material along the direction of combustion wave motion, as well as for calculating and visualizing the 3D-structure of the distribution of synthesized intermetallic interlayers at the interface in nanoparticles with the Ni-Al "core-shell" structure (and similarly for Ti-Al) allows, in contrast to the OVITO package, to detect heterophase intermetallic structures in such systems. As a result of a large series of computational experiments on simulation of microkinetics in the studied nanoscale Ni-Al and Ti-Al systems, it has been established that the software package created by the author with support for parallel computing, which, in addition to the licensed packages LAMMPS and OVITO, integrates author's software modules, has new broader functionality in the methodological aspect of the study of the problems of physical chemistry of the SHS process and is a vivid example of the created software engineering tools in this area of research. read less NOT USED (high confidence) H. Jo et al., “Direct strain correlations at the single-atom level in three-dimensional core-shell interface structures,” Nature Communications. 2022. link Times cited: 8 NOT USED (high confidence) G. Poletaev, Y. Bebikhov, A. Semenov, and M. Starostenkov, “Self-diffusion in melts of Ni-Al and Ti-Al systems: molecular dynamics study,” Letters on Materials. 2021. link Times cited: 3 Abstract: Self-diffusion in liquid alloys of Ni-Al and Ti-Al systems, … read moreAbstract: Self-diffusion in liquid alloys of Ni-Al and Ti-Al systems, depending on the concentration of the components, as well as in pure metals Al, Ni, and Ti, has been studied using the molecular dynamics method. Knowledge of the diffusion parameters in melts of binary systems, such as Ni-Al and Ti-Al, is necessary for a more detailed understanding and prediction of the processes occurring during combustion synthesis and in the manufacture of wares by melt casting. For the considered systems, self-diffusion characteristics (activation energy and preexponential factor in the corresponding Arrhenius equation) are found separately for atoms of different types. Good agreement of diffusion characteristics with experimental data was obtained for pure metal melts, which indicates the physical realism of the molecular dynamics model and EAM potentials used. In addition to pure metals, three component ratios were considered for each system: A 75 B 25 , A 50 B 50 and A 25 B 75 . According to the data obtained, the activation energy of diffusion substantially depends on the concentration of the components, and the highest, among the considered compositions, for Ni 75 Al 25 for Ni-Al system and for Ti 50 Al 50 for Ti-Al system. At the same time, no significant predominance of diffusion mobility of atoms of different types was observed for all the mixture compositions considered. read less NOT USED (high confidence) T. Hammerschmidt, J. Rogal, E. Bitzek, and R. Drautz, “Atomic-scale modeling of superalloys,” Nickel Base Single Crystals Across Length Scales. 2021. link Times cited: 1 NOT USED (high confidence) A. Leineweber, A. Walnsch, P. Fischer, and H. Schumann, “Crystallography of Fe–Mn–Al–Ni Shape Memory Alloys,” Shape Memory and Superelasticity. 2021. link Times cited: 2 NOT USED (high confidence) C. Luo and Y. Zhang, “Simultaneously enhanced reaction temperature and velocity of self-propagating high-temperature synthesis via Joule-heat induced multi-channel heat flow,” Journal of Applied Physics. 2021. link Times cited: 1 Abstract: Simultaneous enhancement of reaction temperature and velocit… read moreAbstract: Simultaneous enhancement of reaction temperature and velocity of self-propagating high-temperature synthesis is still a challenge. Here, we propose a general method based on the Joule-heat induced multi-channel heat flow to simultaneously increase the reaction temperature and velocity of self-propagating high-temperature synthesis. A designed surface structure induces multi-channel Joule-heat accumulation at the surface of reaction components and subsequently multi-channel heat flow during the self-propagating processes. Multi-channel heat flow leads to the formation of two combustion stages: the self-propagating process and the Joule-heat induced grain growth, leading to an enhancement of the maximum reaction temperature up to 67%. Meanwhile, multi-channel heat flow will reduce the propagation distance of the reaction wave and the heat conduction between heat flow channels will increase the temperature of the reaction components, in turn, resulting in an increase in the reaction velocity that is five times higher. We expect that our findings will pave the way for the future application of self-propagating high-temperature synthesis in industries. read less NOT USED (high confidence) A. Fourmont, O. Politano, S. L. Gallet, C. Desgranges, and F. Baras, “Reactivity of Ni–Al nanocomposites prepared by mechanical activation: A molecular dynamics study,” Journal of Applied Physics. 2021. link Times cited: 3 Abstract: High energy ball milling of metallic powders leads to high r… read moreAbstract: High energy ball milling of metallic powders leads to high reactivity in the milled mixture. The reaction is often faster and starts at a lower temperature. However, the mechanisms responsible for this high reactivity are not yet completely understood. The aim of this study is to evaluate one of the possible activating factors of this heightened reactivity: nano-scale mixing of the reagents. Molecular dynamics was used to analyze the role of an amorphous Ni–Al mixing layer, mimicking the powder microstructure after milling, between two Ni layers. The impact of temperature and stoichiometry was investigated in relation to the formation of the B 2-NiAl intermetallic compound. At low temperatures, pre-mixing does not seem to slow down the diffusion of Ni atoms in an amorphous Al region. Homogeneous nucleation was observed in this peculiar milled microstructure. These two phenomena explain why the nano-scale mixing observed experimentally after high energy milling is indeed an activating factor in the reactivity of metallic systems such as Ni–Al. read less NOT USED (high confidence) J. Feng et al., “A molecular dynamics study on the chemical reaction of Ni/Al reactive intermetallics,” Journal of Applied Physics. 2020. link Times cited: 4 Abstract: The chemical reaction mechanism of Ni/Al composites, referri… read moreAbstract: The chemical reaction mechanism of Ni/Al composites, referring to the exothermic mechanism and intermetallic-forming mechanism, is investigated by using molecular dynamics simulation. During the exothermic process, the influences of Ni/Al atomic ratios and crystallographic orientations on the exothermic reaction are systematically investigated. The exothermic mechanism can be explained by the atomic diffusion that increases the quantity of Ni–Al chemical bonds. There are two pathways to form the intermetallic phase during the chemical reaction. One is the atomic diffusion that forms the B2 NiAl phase at the interface. The other way is quenching the sample to the room temperature, but the type of intermetallic phases depends on the Ni/Al atomic ratio and ignition temperature. read less NOT USED (high confidence) V. Jordan, И. В. Иванович, I. Shmakov, and Ш. И. Александрович, “Computer molecular-dynamic simulation of shs microkinetics in the atomic structure with a checkerboard-like arrangement of nanoscale blocks of Ni and Al atoms,” Yugra State University Bulletin. 2020. link Times cited: 0 Abstract: The article presents the results of computer simulation of t… read moreAbstract: The article presents the results of computer simulation of the propagation of the combustion wave of "self-propagating high-temperature synthesis (SHS)" process in an atomic layered structure. In each layer of the structure, nanosized blocks of two types alternate: a block of the first type is composed as a packet of unit cells of Ni atoms, and a block of the second type is composed of a packet of elementary cells of Al atoms. In each pair of layers adjacent to each other, sequences of alternating blocks of two types are shifted relative to each other by one block, so the full layered structure of the layers with alternating blocks in them is associated with a chessboard pattern. Computer simulation of SHS in such a structure was carried out using the LAMMPS software package taking into account parallel computations, which uses the molecular dynamics method and the interatomic interaction potential in the embedded atom" model (EAM). In addition to the LAMMPS package, the authors implemented program procedures for calculating the temperature and density profiles of the substance along the motion direction of the SHS combustion wave front, which made it possible to carry out temperature analysis of the SHS microkinetics (to estimate the velocity of the combustion wave front) and recognition of intermetallic phases in the reaction volume of the Ni-Al system when using the OVITO package. read less NOT USED (high confidence) J. Martí and B. Díaz, “Efficient recursive Adams–Bashforth methods in molecular dynamics simulations of N-body systems interacting through pairwise potentials,” Molecular Simulation. 2020. link Times cited: 1 Abstract: ABSTRACT A recursive multistep Adams–Bashforth method applie… read moreAbstract: ABSTRACT A recursive multistep Adams–Bashforth method applied to the Molecular Dynamics simulations of N-body systems interacting through pairwise force fields is introduced and analysed. Equations of motion are obtained using a set of Cartesian coordinates solved by means of an Adams–Bashforth numerical integration scheme of order s, which requires the iterative computation of function time derivatives. The proposed algorithm has been implemented using a programming approach that makes it possible to re-use a source code resulting in small codes, easy to maintain. Practical examples and benchmarks that illustrate the performance of these implementations are included. The study of its performance gives clues to evaluate its efficiency and precision. Numerical tests for a N-particle system are made on the equilibrium configuration of liquid argon near its triple point at 86.5 K and 0.021 Å . In most cases, the algorithms here presented outperform those implemented traditionally as the Gear corrector-predictor or the Verlet family, leading to important savings in terms of total computation times and significantly increasing the numerical precision obtained with standard algorithms. read less NOT USED (high confidence) S. J. Honrao, S. Xie, and R. Hennig, “Augmenting machine learning of energy landscapes with local structural information,” Journal of Applied Physics. 2020. link Times cited: 13 Abstract: We present a machine learning approach for accurately predic… read moreAbstract: We present a machine learning approach for accurately predicting formation energies of binary compounds in the context of crystal structure predictions. The success of any machine learning model depends significantly on the choice of representation used to encode the relevant physical information into machine-learnable data. We test different representation schemes based on partial radial and angular distribution functions (RDF+ADF) on Al–Ni and Cd–Te structures generated using our genetic algorithm for structure prediction. We observe a remarkable improvement in predictive accuracy upon transitioning from global to atom-centered representations, resulting in a threefold decrease in prediction errors. We show that a support vector regression model using a combination of atomic radial and angular distribution functions performs best at the formation energy prediction task, providing small root mean squared errors of 3.9 meV/atom and 10.9 meV/atom for Al–Ni and Cd–Te, respectively. We test the performance of our models against common traditional descriptors and find that RDF- and ADF-based representations significantly outperform many of those in the prediction of formation energies. The high accuracy of predictions makes our machine learning models great candidates for the exploration of energy landscapes. read less NOT USED (high confidence) Y. Zhang et al., “Sintering reaction and microstructure of MAl (M = Ni, Fe, and Mg) nanoparticles through molecular dynamics simulation,” Chinese Physics B. 2020. link Times cited: 4 NOT USED (high confidence) L. Hui, D. Wan, and L. Yi, “Molecular Dynamics Study of Tension Process of Ni-Based Superalloy,” Acta Metallurgica Sinica (english Letters). 2020. link Times cited: 5 NOT USED (high confidence) H. Li, W. Du, and Y. Liu, “Molecular Dynamics Study of Tension Process of Ni-Based Superalloy,” Acta Metallurgica Sinica (English Letters). 2020. link Times cited: 4 NOT USED (high confidence) Z. Wang, F. Yang, J. Shang, N. Wei, L. Kou, and C. Li, “Mechanical properties of CNT-reinforced Ni3Al composites: the role of chirality, temperature, and volume fraction,” Journal of Physics: Condensed Matter. 2020. link Times cited: 5 Abstract: is an extremely significant reinforcing phase in nickel-base… read moreAbstract: is an extremely significant reinforcing phase in nickel-based single crystal superalloys. As an alternative strengthening method to improve its mechanical properties, carbon nanotube (CNT)-reinforced composites have recently been synthesized in experiments. Here, in order to explore the corresponding influence factors and the underlying mechanism, tensile and compressive mechanical properties of CNT- composites are systematically investigated by using molecular dynamics simulations. It is shown that the dispersion of a minor fraction of a CNT into matrix leads to a sufficient enhancement in the stiffness of CNT- composites compared with the pure . It is demonstrated that CNT reinforcement takes effect in the elastic stage under compression while it works continuously during tension. Compared with armchair CNTs, zigzag CNTs are predicted to provide more strength for raising the elastic modulus while armchair CNTs can provide superior elongation. Particularly, CNTs are found to hinder the generation of slip bands under tensile loading owing to the robust interfacial interactions. Furthermore, quantitative analysis reveals that the impact of volume fraction of CNT is much more significant than the size effect. The role of chirality, temperature and volume fraction of CNT obtained in the present work could provide beneficial references for subsequent theoretical and experimental investigations, and shed some light on the design of CNT-reinforced composites in nanoscale engineering. read less NOT USED (high confidence) G. D. Smith, D. Bedrov, and J. Hooper, “Molecular dynamics simulations of isothermal reactions in Al/Ni nanolaminates.,” The Journal of chemical physics. 2019. link Times cited: 6 Abstract: Molecular dynamics simulations of reactions in Al/Ni layered… read moreAbstract: Molecular dynamics simulations of reactions in Al/Ni layered systems have been carried out under isothermal conditions for a wide range of temperatures and several system sizes. An embedded atom method potential, known to reasonably reproduce the phase behavior of Al/Ni, was employed. Simulations revealed reaction mechanisms involving an initial fast process and much slower more complex longer-time reactions. The initial reaction process consists of diffusion of Ni from the pure solid Ni phase into the molten Al phase, resulting in the formation of an Al-rich Al/Ni liquid. The initial reaction ends when the Al/Ni liquid becomes saturated in Ni and solid Al/Ni phases begin to form at the interfaces between the pure solid Ni phase and the Al/Ni liquid. The growth of these solid phases is intrinsically slow compared to the formation of the liquid and is further slowed by the need for Ni to diffuse through the growing interfacial Al/Ni solid phases. Analysis of the initial Al/Ni liquid forming process indicates Fickian behavior with the Ni diffusion coefficient exhibiting Arrhenius temperature dependence. The longer-time slow reaction process(es) resulting in the growth of Al/Ni solid phases do not lend themselves to detailed numerical analysis because of the complex dependence of the Ni transport on the detailed nature of the interfacial layers. read less NOT USED (high confidence) M. Ångqvist, J. Rahm, L. Gharaee, and P. Erhart, “Structurally driven asymmetric miscibility in the phase diagram of W-Ti,” Physical Review Materials. 2019. link Times cited: 13 Abstract: Phase diagrams for multi-component systems represent crucial… read moreAbstract: Phase diagrams for multi-component systems represent crucial information for understanding and designing materials but are very time consuming to assess experimentally. Computational modeling plays an increasingly important role in this regard but has been largely focused on systems with matching lattice structures and/or stable boundary phases. Here, using a combination of density functional theory calculations, alloy cluster expansions, free energy integration, and Monte Carlo simulations, we obtain the phase diagram of W-Ti, a system that features metastable boundary phases on both sides of the phase diagram. We find that the mixing energy on the body-centered cubic (BCC) lattice is asymmetric and negative with a minimum of about -120 meV/atom, whereas for the hexagonal closed packed (HCP) lattice the mixing energy is positive. By combining these data with a model for the vibrational free energy, we propose a revision of the W-rich end of the phase diagram with a much larger solubility of Ti in BCC-W than previous assessments. Finally, by comparison with the W-V and W-Re system we demonstrate how strongly asymmetric phase diagrams can arise from a subtle energy balance of stable and metastable lattice structures. read less NOT USED (high confidence) U. Sarder et al., “Mass and thermal transport in liquid Cu-Ag alloys,” Philosophical Magazine. 2018. link Times cited: 10 Abstract: ABSTRACT In this paper, the diffusion, thermodynamic and the… read moreAbstract: ABSTRACT In this paper, the diffusion, thermodynamic and thermotransport properties in Cu–Ag liquid alloys are extensively investigated with molecular dynamics over a wide composition and temperature range. The simulations are performed with the most reliable EAM potential. The Green-Kubo formalism is employed for calculating transport properties. It is found that the reduced heat of transport in Cu–Ag is very small (about 0.10 eV in absolute value) and almost temperature independent. Further it is found that the interdiffusion coefficient together with both self-diffusion coefficients are almost composition independent. In Cu–Ag, the thermodynamic factor is found to be less than unity whereas the Manning factor is greater than unity (with significant composition and temperature dependence) and their product is very close to 1. read less NOT USED (high confidence) C. Howells and Y. Mishin, “Angular-dependent interatomic potential for the binary Ni–Cr system,” Modelling and Simulation in Materials Science and Engineering. 2018. link Times cited: 26 Abstract: A new interatomic potential has been developed for the Ni–Cr… read moreAbstract: A new interatomic potential has been developed for the Ni–Cr system in the angular-dependent potential (ADP) format by fitting the potential parameters to a set of experimental and first-principles data. The ADP potential reproduces a wide range of properties of both elements as well as binary alloys with reasonable accuracy, including thermal and mechanical properties, defects, melting points of Ni and Cr, and the Ni–Cr phase diagram. The potential can be used for atomistic simulations of solidification, mechanical behavior and microstructure of the Ni-based and Cr-based phases as well as two-phase alloys. read less NOT USED (high confidence) F. Baras, V. Turlo, O. Politano, S. Vadchenko, A. Rogachev, and A. Mukasyan, “SHS in Ni/Al Nanofoils: A Review of Experiments and Molecular Dynamics Simulations,” Advanced Engineering Materials. 2018. link Times cited: 38 Abstract: Non‐isothermal processes in nanometric metallic multilayers … read moreAbstract: Non‐isothermal processes in nanometric metallic multilayers are reviewed, both experimentally and theoretically. The Ni/Al nanofoil is considered as a model system. On the one hand, the experimental methods of elaboration and analysis are presented and, on the other hand, the modeling approach at the macroscopic and atomic scale. The basic experimental features are reported together with recent achievements. Molecular dynamics investigation of the reactivity of Ni/Al systems is reported for bulk systems and nanosystems including nanoparticles, nanowires, nanofilms, and multilayers. The focus is on atomic‐scale modeling versus experiments. Molecular dynamics approaches allow us to elucidate the mechanisms of non‐isothermal processes occurring in nanoscale systems, such as phase transformations and self‐propagation reactions. read less NOT USED (high confidence) T. Ahmed, W. Wang, R. Kozubski, Z.-kui Liu, I. Belova, and G. Murch, “Interdiffusion and thermotransport in Ni–Al liquid alloys,” Philosophical Magazine. 2018. link Times cited: 10 Abstract: ABSTRACT In this paper, we present extensive self-consistent… read moreAbstract: ABSTRACT In this paper, we present extensive self-consistent results of molecular dynamics (MD) simulations of diffusion and thermotransport properties of Ni–Al liquid alloys. We develop a new formalism that allows easy connection between results of the MD simulations and the real experiments. In addition, this formalism can be extended to the case of ternary and higher component liquid alloys. We focus on the temperature and composition dependence of the self-diffusion coefficients, interdiffusion coefficients, thermodynamic factor, Manning factor and the reduced heat of transport. The two latter quantities both represent measures of the off-diagonal Onsager phenomenological coefficients. The Manning factor and the reduced heat of transport can be related to experimentally obtainable quantities provided the thermodynamic factor is available. The simulation results for the reduced heat of transport show that for all compositions, in the presence of a temperature gradient, Ni tends to migrate to the cold end. This is in agreement with an available experimental study for a Ni21.5Al78.5 melt (only qualitative result is available so far). read less NOT USED (high confidence) L. Hale, “Comparing Modeling Predictions of Aluminum Edge Dislocations: Semidiscrete Variational Peierls–Nabarro Versus Atomistics,” JOM. 2018. link Times cited: 7 NOT USED (high confidence) C. Zeni et al., “Building machine learning force fields for nanoclusters.,” The Journal of chemical physics. 2018. link Times cited: 40 Abstract: We assess Gaussian process (GP) regression as a technique to… read moreAbstract: We assess Gaussian process (GP) regression as a technique to model interatomic forces in metal nanoclusters by analyzing the performance of 2-body, 3-body, and many-body kernel functions on a set of 19-atom Ni cluster structures. We find that 2-body GP kernels fail to provide faithful force estimates, despite succeeding in bulk Ni systems. However, both 3- and many-body kernels predict forces within an ∼0.1 eV/Å average error even for small training datasets and achieve high accuracy even on out-of-sample, high temperature structures. While training and testing on the same structure always provide satisfactory accuracy, cross-testing on dissimilar structures leads to higher prediction errors, posing an extrapolation problem. This can be cured using heterogeneous training on databases that contain more than one structure, which results in a good trade-off between versatility and overall accuracy. Starting from a 3-body kernel trained this way, we build an efficient non-parametric 3-body force field that allows accurate prediction of structural properties at finite temperatures, following a newly developed scheme [A. Glielmo et al., Phys. Rev. B 95, 214302 (2017)]. We use this to assess the thermal stability of Ni19 nanoclusters at a fractional cost of full ab initio calculations. read less NOT USED (high confidence) J. Amodeo and K. Lizoul, “Mechanical properties and dislocation nucleation in nanocrystals with blunt edges,” Materials & Design. 2017. link Times cited: 36 NOT USED (high confidence) E. Levchenko, T. Ahmed, and A. Evteev, “Composition dependence of diffusion and thermotransport in Ni-Al melts: A step towards molecular dynamics assisted databases,” Acta Materialia. 2017. link Times cited: 21 NOT USED (high confidence) W. Nöhring and W. Curtin, “Dislocation cross-slip in fcc solid solution alloys,” Acta Materialia. 2017. link Times cited: 65 NOT USED (high confidence) R. Dikken, B. Thijsse, and L. Nicola, “Friction of atomically stepped surfaces,” Physical Review B. 2017. link Times cited: 5 Abstract: The friction behavior of atomically stepped metal surfaces u… read moreAbstract: The friction behavior of atomically stepped metal surfaces under contact loading is studied using molecular dynamics simulations. While real rough metal surfaces involve roughness at multiple length scales, the focus of this paper is on understanding friction of the smallest scale of roughness: atomic steps. To this end, periodic stepped Al surfaces with different step geometry are brought into contact and sheared at room temperature. Contact stress that continuously tries to build up during loading, is released with fluctuating stress drops during sliding, according to the typical stick-slip behavior. Stress release occurs not only through local slip, but also by means of step motion. The steps move along the contact, concurrently resulting in normal migration of the contact. The direction of migration depends on the sign of the step, i.e., its orientation with respect to the shearing direction. If the steps are of equal sign, there is a net migration of the entire contact accompanied by significant vacancy generation at room temperature. The stick-slip behavior of the stepped contacts is found to have all the characteristic of a self-organized critical state, with statistics dictated by step density. For the studied step geometries, frictional sliding is found to involve significant atomic rearrangement through which the contact roughness is drastically changed. This leads for certain step configurations to a marked transition from jerky sliding motion to smooth sliding, making the final friction stress approximately similar to that of a flat contact. read less NOT USED (high confidence) K. Choudhary, F. Y. Congo, T. Liang, C. Becker, R. Hennig, and F. Tavazza, “Evaluation and comparison of classical interatomic potentials through a user-friendly interactive web-interface,” Scientific Data. 2017. link Times cited: 21 NOT USED (high confidence) J. Guénolé, A. Prakash, and E. Bitzek, “Influence of intrinsic strain on irradiation induced damage: the role of threshold displacement and surface binding energies,” Materials & Design. 2016. link Times cited: 10 NOT USED (high confidence) S. Trady, A. Hasnaoui, M. Mazroui, and K. Saadouni, “Local atomic structures of single-component metallic glasses,” The European Physical Journal B. 2016. link Times cited: 21 NOT USED (high confidence) M. D. Grapes and T. Weihs, “Exploring the reaction mechanism in self-propagating Al/Ni multilayers by adding inert material,” Combustion and Flame. 2016. link Times cited: 31 NOT USED (high confidence) E. Levchenko et al., “Influence of the interatomic potential on thermotransport in binary liquid alloys: case study on NiAl,” Philosophical Magazine. 2016. link Times cited: 14 Abstract: Equilibrium molecular dynamics simulation in conjunction wit… read moreAbstract: Equilibrium molecular dynamics simulation in conjunction with the Green-Kubo formalism is employed to study the transport properties of a model Ni50Al50 melt with the embedded-atom method potential developed in [G.P. Purja Pun, Y. Mishin, Phil. Mag., 2009, 89, 3245]. The principal objective of the work is to quantitatively characterise and analyse thermotransport in the system, i.e. diffusion driven by a temperature gradient. In addition, direct phenomenological coefficients for mass and thermal transport are also evaluated and analysed in the process. Furthermore, the results obtained are compared with previously published data for a different model of Ni50Al50 melt with an alternative embedded-atom method potential for the alloy as well as with experiment where possible. It is found that both potentials are able to consistently predict both direct transport coefficients over a wide temperature range. However, these two potentials are found to be inconsistent in characterising the cross-coupled heat and mass transport, predicting even different directions (sign) of the heat of thermotransport. The origin of this difference is discussed in the paper in detail. read less NOT USED (high confidence) V. M. Bezpal’chuk, S. Marchenko, O. Rymar, O. O. Bogatyryov, and A. Gusak, “Problem of a Choice of the First Phase in Reaction between Nanofilms of Nickel and Aluminium,” Metallofizika I Noveishie Tekhnologii. 2016. link Times cited: 0 NOT USED (high confidence) A. Shirinyan, “Concept of Size-Dependent Atomic Interaction Energies for Solid Nanomaterials: Thermodynamic and Diffusion Aspects,” Metallofizika I Noveishie Tekhnologii. 2016. link Times cited: 3 NOT USED (high confidence) J. Crocombette, L. Brutzel, D. Simeone, and L. Lunéville, “Molecular dynamics simulations of high energy cascade in ordered alloys: Defect production and subcascade division,” Journal of Nuclear Materials. 2016. link Times cited: 21 NOT USED (high confidence) R. E. Miller, E. Tadmor, J. Gibson, N. Bernstein, and F. Pavia, “Molecular dynamics at constant Cauchy stress.,” The Journal of chemical physics. 2016. link Times cited: 18 Abstract: The Parrinello-Rahman algorithm for imposing a general state… read moreAbstract: The Parrinello-Rahman algorithm for imposing a general state of stress in periodic molecular dynamics simulations is widely used in the literature and has been implemented in many readily available molecular dynamics codes. However, what is often overlooked is that this algorithm controls the second Piola-Kirchhoff stress as opposed to the true (Cauchy) stress. This can lead to misinterpretation of simulation results because (1) the true stress that is imposed during the simulation depends on the deformation of the periodic cell, (2) the true stress is potentially very different from the imposed second Piola-Kirchhoff stress, and (3) the true stress can vary significantly during the simulation even if the imposed second Piola-Kirchhoff is constant. We propose a simple modification to the algorithm that allows the true Cauchy stress to be controlled directly. We then demonstrate the efficacy of the new algorithm with the example of martensitic phase transformations under applied stress. read less NOT USED (high confidence) J. Roth, H. Trebin, A. Kiselev, and D. Rapp, “Laser ablation of Al–Ni alloys and multilayers,” Applied Physics A. 2016. link Times cited: 10 NOT USED (high confidence) A. Evteev, E. Levchenko, L. Momenzadeh, I. Belova, and G. Murch, “Insight into lattice thermal impedance via equilibrium molecular dynamics: case study on Al,” Philosophical Magazine. 2016. link Times cited: 4 Abstract: Using results of equilibrium molecular dynamics simulation i… read moreAbstract: Using results of equilibrium molecular dynamics simulation in conjunction with the Green–Kubo formalism, we present a general treatment of thermal impedance of a crystal lattice with a monatomic unit cell. The treatment is based on an analytical expression for the heat current autocorrelation function which reveals, in a monatomic lattice, an energy gap between the origin of the phonon states and the beginning of the energy spectrum of the so-called acoustic short-range phonon modes. Although, we consider here the f.c.c. Al model as a case example, the analytical expression is shown to be consistent for different models of elemental f.c.c. crystals over a wide temperature range. Furthermore, we predict a frequency ‘window’ where the thermal waves can be generated in a monatomic lattice by an external periodic temperature perturbation. read less NOT USED (high confidence) V. Yamakov et al., “Multiscale modeling of sensory properties of Co–Ni–Al shape memory particles embedded in an Al metal matrix,” Journal of Materials Science. 2016. link Times cited: 24 NOT USED (high confidence) A. Kumar et al., “Charge optimized many-body (COMB) potential for dynamical simulation of Ni–Al phases,” Journal of Physics: Condensed Matter. 2015. link Times cited: 18 Abstract: An interatomic potential for the Ni–Al system is presented w… read moreAbstract: An interatomic potential for the Ni–Al system is presented within the third-generation charge optimized many-body (COMB3) formalism. The potential has been optimized for Ni3Al, or the γ′ phase in Ni-based superalloys. The formation energies predicted for other Ni–Al phases are in reasonable agreement with first-principles results. The potential further predicts good mechanical properties for Ni3Al, which includes the values of the complex stacking fault (CSF) and the anti-phase boundary (APB) energies for the (1 1 1) and (1 0 0) planes. It is also used to investigate dislocation propagation across the Ni3Al (1 1 0)–Ni (1 1 0) interface, and the results are consistent with simulation results reported in the literature. The potential is further used in combination with a recent COMB3 potential for Al2O3 to investigate the Ni3Al (1 1 1)–Al2O3 (0 0 01) interface, which has not been modeled previously at the classical atomistic level due to the lack of a reactive potential to describe both Ni3Al and Al2O3 as well as interactions between them. The calculated work of adhesion for this interface is predicted to be 1.85 J m−2, which is in agreement with available experimental data. The predicted interlayer distance is further consistent with the available first-principles results for Ni (1 1 1)–Al2O3 (0 0 0 1). read less NOT USED (high confidence) G. P. P. Pun, V. Yamakov, and Y. Mishin, “Interatomic potential for the ternary Ni–Al–Co system and application to atomistic modeling of the B2–L10 martensitic transformation,” Modelling and Simulation in Materials Science and Engineering. 2015. link Times cited: 80 Abstract: Ni–Al–Co is a promising system for ferromagnetic shape memor… read moreAbstract: Ni–Al–Co is a promising system for ferromagnetic shape memory applications. This paper reports on the development of a ternary embedded-atom potential for this system by fitting to experimental and first-principles data. Reasonably good agreement is achieved for physical properties between values predicted by the potential and values known from experiment and/or first-principles calculations. The potential reproduces basic features of the martensitic phase transformation from the B2-ordered high-temperature phase to a tetragonal CuAu-ordered low-temperature phase. The compositional and temperature ranges of this transformation and the martensite microstructure predicted by the potential compare well with existing experimental data. These results indicate that the proposed potential can be used for simulations of the shape memory effect in the Ni–Al–Co system. read less NOT USED (high confidence) J. Rogal et al., “Perspectives on point defect thermodynamics,” physica status solidi (b). 2014. link Times cited: 54 Abstract: We review and discuss methods for including the role of poin… read moreAbstract: We review and discuss methods for including the role of point defects in calculations of the free energy, composition and phase stability of elements and compounds. Our principle aim is to explain and to reconcile, with examples, the perspectives on this problem that are often strikingly different between exponents of CALPHAD, and others working in the overlapping fields of physics, chemistry and materials science. Current methodologies described here include the compound energy formalism of CALPHAD, besides the rather different but related canonical and grand‐canonical formalisms. We show how the calculation of appropriate defect formation energies should be formulated, how they are included in the different formalisms and in turn how these yield equilibrium defect concentrations and their contribution to free energies and chemical potentials. Furthermore, we briefly review the current state‐of‐the‐art and challenges in determining point defect properties from first‐principles calculations as well as from experimental measurements. read less NOT USED (high confidence) Y. Mishin, “Calculation of the γ/γ′ interface free energy in the Ni–Al system by the capillary fluctuation method,” Modelling and Simulation in Materials Science and Engineering. 2013. link Times cited: 41 Abstract: Monte Carlo computer simulations with an embedded-atom poten… read moreAbstract: Monte Carlo computer simulations with an embedded-atom potential are applied to study coherent γ/γ′ interfaces in the Ni–Al system. The (1 0 0) interface free energy has been extracted from the power spectrum of equilibrium shape fluctuations (capillary waves) and found to decrease with temperature from about 20 mJ m−2 at 550 K to about 10 mJ m−2 at 1200 K. These numbers are in reasonable agreement with existing experimental data. Strengths and weaknesses of the capillary wave method are discussed. read less NOT USED (high confidence) A. Shirinyan and Y. Bilogorodskyy, “Atom-atom interactions in continuous metallic nanofilms,” The Physics of Metals and Metallography. 2012. link Times cited: 3 NOT USED (high confidence) S. Izvekov and B. Rice, “Free-energy based pair-additive potentials for bulk Ni-Al systems: application to study Ni-Al reactive alloying.,” The Journal of chemical physics. 2012. link Times cited: 11 Abstract: We present new numerical pair-additive Al, Ni, and Al-Ni pot… read moreAbstract: We present new numerical pair-additive Al, Ni, and Al-Ni potentials by force-matching (FM) ionic force and virial data from single (bulk liquid) phase ab initio molecular dynamics (MD) simulations using the Born-Oppenheimer method. The potentials are represented by piece-wise functions (splines) and, therefore, are not constrained to a particular choice of analytical functional form. The FM method with virial constraint naturally yields a potential which maps out the ionic free-energy surface of the reference ensemble. To further improve the free energetics of the FM ensemble, the FM procedure is modified to bias the potentials to reproduce the experimental melting temperatures of the reference (FCC-Al, FCC-Ni, B2-NiAl) phases, the only macroscopic data included in the fitting set. The performance of the resultant potentials in simulating bulk metallic phases is then evaluated. The new model is applied to perform MD simulations of self-propagating exothermic reaction in Ni-Al bilayers at P = 0-5 GPa initiated at T = 1300 K. Consistent with experimental observations, the new model describes realistically a sequence of peritectic phase transformations throughout the reaction and at a realistic rate. The reaction proceeds through interlayer diffusion of Al and Ni atoms at the interface with formation of B2-NiAl in the Al melt. Such material responses have, in the past, been proven to be difficult to observe with then-existing potentials. read less NOT USED (high confidence) G. P. P. Pun and Y. Mishin, “Molecular dynamics simulation of the martensitic phase transformation in NiAl alloys,” Journal of Physics: Condensed Matter. 2010. link Times cited: 36 Abstract: Using molecular dynamics simulations with an embedded-atom i… read moreAbstract: Using molecular dynamics simulations with an embedded-atom interatomic potential, we study the effect of chemical composition and uniaxial mechanical stresses on the martensitic phase transformation in Ni-rich NiAl alloys. The martensitic phase has a tetragonal crystal structure and can contain multiple twins arranged in domains and plates. The transformation is reversible and is characterized by a significant temperature hysteresis. The magnitude of the hysteresis depends on the chemical composition and stress. We show that applied compressive and tensile stresses reduce and can even eliminate the hysteresis. Crystalline defects such as free surfaces, dislocations and anti-phase boundaries reduce the martensitic transformation temperature and affect the microstructure of the martensite. Their effect can be explained by heterogeneous nucleation of the new phase in defected regions. read less NOT USED (high confidence) L. Proville and S. Patinet, “Atomic-scale models for hardening in fcc solid solutions,” Physical Review B. 2010. link Times cited: 31 Abstract: Atomic-scale simulations are associated with an elastic line… read moreAbstract: Atomic-scale simulations are associated with an elastic line model to analyze thoroughly the pinning strength experienced by an edge dislocation in some face-centered-cubic solid solutions, Al Mg and Ni Al with solute concentration comprise between 1 and 10 at. %. The one-dimensional elastic line model is developed to sketch out the details of the atomic scale. The account of such details is shown to yield a proper description of the dislocation statistics for the different systems. The quantitative departure between hardening in Al Mg and Ni Al is then demonstrated to hinge on the difference in the short-range interaction between the partial dislocations and the isolated impurities. It is also shown that an accurate description of the solidsolution hardening requires the account for the dislocation geometry and the dislocation interaction with clusters of solute atoms. The elastic line model allows us to perform some computations at the microscopic scales meanwhile accounting for the most important atomic details. A comparison with experimental data is attempted. read less NOT USED (high confidence) J.-ping Du, C.-yu Wang, C.-yu Wang, and T. Yu, “Construction and application of multi-element EAM potential (Ni–Al–Re) in γ/γ′ Ni-based single crystal superalloys,” Modelling and Simulation in Materials Science and Engineering. 2012. link Times cited: 44 Abstract: Based on experiments and first-principles calculations, a Ni… read moreAbstract: Based on experiments and first-principles calculations, a Ni–Al–Re system embedded atom method (EAM) potential is constructed for the γ(Ni)/γ′(Ni3Al) superalloy. The contribution of the inner elastic constants is considered in the fitting of Re with a hexagonal close-packed structure. Using this potential, point defects, planar defects and lattice misfit of γ(Ni) and γ′(Ni3Al) are investigated. The interaction between Re and the misfit dislocation of the γ(Ni)/γ′(Ni3Al) system is also calculated. We conclude that the embedding energy has an important effect on the properties of the alloys, such as the planar fault energies of Ni3Al, by considering the relationship between the charge transfer calculated from first-principles, the elastic constants of Ni3Al and the host electron density of the EAM potential. The multi-element potential predicts that Re does not form clusters in γ(Ni), which is consistent with recent experiments and first-principles calculations. read less
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