Finnis-Sinclair potential (LAMMPS cubic hermite tabulation) for the Cu-Zr system developed by Mendelev, Sordelet and Kramer (2007) v005

Dan J. Sordelet; Matthew J. Kramer; Mikhail I. Mendelev

doi:10.25950/8556dbaf

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EAM_Dynamo_MendelevSordeletKramer_2007_CuZr__MO_120596890176_005

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Interatomic potential for Copper (Cu), Zirconium (Zr).
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Title A single sentence description.	Finnis-Sinclair potential (LAMMPS cubic hermite tabulation) for the Cu-Zr system developed by Mendelev, Sordelet and Kramer (2007) v005
Description A short description of the Model describing its key features including for example: type of model (pair potential, 3-body potential, EAM, etc.), modeled species (Ac, Ag, ..., Zr), intended purpose, origin, and so on.	We propose a method of using atomistic computer simulations to obtain partial pair correlation functions from wide angle diffraction experiments with metallic liquids and their glasses. In this method, a model is first created using a semiempirical interatomic potential and then an additional atomic force is added to improve the agreement with experimental diffraction data. To illustrate this approach, the structure of an amorphous Cu64.5Zr35.5 alloy is highlighted, where we present the results for the semiempirical many-body potential and fitting to x-ray diffraction data. While only x-ray diffraction data were used in the present work, the method can be easily adapted to the case when there are also data from neutron diffraction or even in combination. Moreover, this method can be employed in the case of multicomponent systems when the data of several diffraction experiments can be combined. Note that the version published in [M.I. Mendelev, M.J. Kramer, R.T. Ott, D.J. Sordelet, D. Yagodin and P. Popel, Phil. Mag. 89, 967-987 (2009).] is better for simulation of liquid/glass structure.
Species The supported atomic species.	Cu, Zr
Disclaimer A statement of applicability provided by the contributor, informing users of the intended use of this KIM Item.	The authors note in the paper that this potential was never intended for serious simulation. An improved Cu-Zr model can be found in KIM item https://openkim.org/id/MO_609260676108_000.
Content Origin	http://www.ctcms.nist.gov/potentials/Cu.html

Contributor	Mikhail I. Mendelev
Maintainer	Mikhail I. Mendelev
Developer	Dan J. Sordelet Matthew J. Kramer Mikhail I. Mendelev
Published on KIM	2018
How to Cite	Click here to download this citation in BibTeX format.
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See the Deep Citation documentation for more information. 282 Citations (243 used) Show Model Used Show All Help us to determine which of the papers that cite this potential actually used it to perform calculations. If you know, click the . D. Şopu, X. Yuan, F. Moitzi, M. Stoica, and J. Eckert, “Structure–Property Relationships in Shape Memory Metallic Glass Composites,” Materials. 2019. link Times cited: 23 Abstract: Metallic glass composites with shape memory crystals show en… read more Abstract: Metallic glass composites with shape memory crystals show enhanced plasticity and work-hardening capability. We investigate the influence of various critical structural aspects such as, the density of crystalline precipitates, their distribution and size, and the structural features and intrinsic properties of the phase on the deformation behavior of metallic amorphous Cu64Zr36 composites with B2 CuZr inclusions using molecular dynamics simulations. We find that a low density of small B2 inclusions with spacing smaller than the critical shear band length controls the formation and distribution of plastic zones in the composite and hinders the formation of critical shear bands. When the free path for shearing allows the formation of mature shear bands a high volume fraction of large B2 precipitates is necessary to stabilize the shear flow and avoid runaway instability. Additionally, we also investigate the deformation mechanism of composites with pure copper crystals for comparison, in order to understand the superior mechanical properties of metallic glass composites with shape memory crystals in more detail. The complex and competing mechanisms of deformation occurring in shape memory metallic glass composites allow this class of materials to sustain large tensile deformation, even though only a low-volume fraction of crystalline inclusions is present. read less K. E. Avila, S. Küchemann, I. A. Alhafez, and H. Urbassek, “Shear-Transformation Zone Activation during Loading and Unloading in Nanoindentation of Metallic Glasses,” Materials. 2019. link Times cited: 26 Abstract: Using molecular dynamics simulation, we study nanoindentatio… read more Abstract: Using molecular dynamics simulation, we study nanoindentation in large samples of Cu–Zr glass at various temperatures between zero and the glass transition temperature. We find that besides the elastic modulus, the yielding point also strongly (by around 50%) decreases with increasing temperature; this behavior is in qualitative agreement with predictions of the cooperative shear model. Shear-transformation zones (STZs) show up in increasing sizes at low temperatures, leading to shear-band activity. Cluster analysis of the STZs exhibits a power-law behavior in the statistics of STZ sizes. We find strong plastic activity also during the unloading phase; it shows up both in the deactivation of previous plastic zones and the appearance of new zones, leading to the observation of pop-outs. The statistics of STZs occurring during unloading show that they operate in a similar nature as the STZs found during loading. For both cases, loading and unloading, we find the statistics of STZs to be related to directed percolation. Material hardness shows a weak strain-rate dependence, confirming previously reported experimental findings; the number of pop-ins is reduced at slower indentation rate. Analysis of the dependence of our simulation results on the quench rate applied during preparation of the glass shows only a minor effect on the properties of STZs. read less P.-wei Wang, H. Li, and L. Yang, “Free Volume Contributing to the Different Yield Behaviors between Tension and Compression Deformations in Metallic Glasses.” 2017. link Times cited: 8 Abstract: The different deformation behaviors in the yield stage, in p… read more Abstract: The different deformation behaviors in the yield stage, in particular, of metallic glasses under uniaxial tension and compression are investigated from an atomic structural perspective, by applying both experimental and simulation methods. A new computational approach for quantitatively calculating free volumes (FVs) in structural models is developed, based on which the manner in which FVs contribute to deformation is studied. It is found that FVs have different expansion behaviors in terms of their saturation sizes and corresponding strain values, which are essential structural causes of different yield behaviors in these two deformations in metallic glasses. read less C. Zhong et al., “Non-localized deformation in CuZr multi-layer amorphous films under tension,” Journal of Alloys and Compounds. 2016. link Times cited: 36 X. Huang, Z. Ling, Y. Wang, and L. Dai, “Intrinsic structural defects on medium range in metallic glasses,” Intermetallics. 2016. link Times cited: 16 D. Şopu, C. Soyarslan, B. Sarac, S. Bargmann, M. Stoica, and J. Eckert, “Structure-property relationships in nanoporous metallic glasses,” Acta Materialia. 2016. link Times cited: 87 M. Sepulveda-Macias, N. Amigo, and G. Gutiérrez, “Onset of plasticity and its relation to atomic structure in CuZr metallic glass nanowire: A molecular dynamics study,” Journal of Alloys and Compounds. 2016. link Times cited: 17 C. Li, Y. Wei, and X. Shi, “Reformation Capability of Short-Range Order and Their Medium-Range Connections Regulates Deformability of Bulk Metallic Glasses,” Scientific Reports. 2015. link Times cited: 4 Z. W. Wu, F. Li, C. Huo, M. Li, W. Wang, and K. Liu, “Critical scaling of icosahedral medium-range order in CuZr metallic glass-forming liquids,” Scientific Reports. 2015. link Times cited: 32 M. Khandpekar, A. Shrivastava, D. Gowtam, M. Mohape, and V. Deshmukh, “Prediction of glass forming ability in Cu xzr 1-x alloys using molecular dynamics.” 2015. link Times cited: 1 Abstract: Binary CuxZr1−x (x = 0.46, 0.50, 0.58, 0.62) alloy systems w… read more Abstract: Binary CuxZr1−x (x = 0.46, 0.50, 0.58, 0.62) alloy systems were developed using a conventional melting route. Molecular dynamics (MD) simulations have been carried out using the embedded atom method (EAM) potentials. Radial distribution function (RDF) and Voronoi calculations have been conceded for amorphous structure verification. The reduced glass transition temperature (Trg) has been determined in order to predict the glass forming ability (GFA) of these alloys. Tl is found to be a better substitute for Tm and the simulated Trg values are seen to be in good agreement with the experimental results in limits of 0.8 – 5.4 %. read less S. Sayad, M. Khanzadeh, G. Alahyarizadeh, and N. Amigo, “A molecular dynamics study on the mechanical response of thermal-pressure rejuvenated CuxZr100−x metallic glasses,” Scientific Reports. 2023. link Times cited: 0 Y.-T. Sun et al., “Distinct relaxation mechanism at room temperature in metallic glass,” Nature Communications. 2023. link Times cited: 4 K. E. Avila, S. Küchemann, R. Pinzón, and H. Urbassek, “Influence of stoichiometry on indentation-induced plasticity in CuZr glasses,” Applied Physics A. 2021. link Times cited: 3 Y. Zhang, J. Li, H. Zhou, Y. Hu, S. Ding, and R. Xia, “Cold welding behavior of metallic glass nanowires: Insights from large-scale numerical simulations,” Journal of Materials Science. 2021. link Times cited: 10 K. E. Avila, V. Vardanyan, and H. Urbassek, “Transition to chip serration in simulated cutting of metallic glasses,” The European Physical Journal B. 2021. link Times cited: 3 A. Abdelmawla, T. Phan, L. Xiong, and A. Bastawros, “A combined experimental and computational analysis on how material interface mediates plastic flow in amorphous/crystalline composites,” Journal of Materials Research. 2021. link Times cited: 3 Abstract: In this work, we study the deformation behavior in amorphous… read more Abstract: In this work, we study the deformation behavior in amorphous/crystalline metallic composites (A/C-MCs) through nanoindentation experiments and molecular dynamic (MD) simulations. The atomic deformation processes in both crystalline (C-) and amorphous (A-) phases near the amorphous-crystalline interface (ACI) are investigated and correlated with the material’s overall constitutive behavior at the microscale. Our major findings are (i) the ACIs enable a co-deformation of the A- and C-phases through “stiffening” the soft phases but “softening” the stiff phases in A/C-MCs through different micro-mechanisms; (ii) there exists an ACI-induced transition zone with a thickness of ~ 10 nm; (iii) the strong coupling between shear transformation zones (STZs) and dislocations can be quantified through carefully designed indentation experiments and simulations; and (iv) the nanoscale MD-simulation-predicted mechanisms can be mapped to the “pop-in” or “excursion” events on the force–indentation depth curves extracted from microscale experiments, although there is a length-scale gap in between. read less W. Wu, D. Şopu, and J. Eckert, “Molecular Dynamics Study of the Nanoindentation Behavior of Cu64Zr36/Cu Amorphous/Crystalline Nanolaminate Composites,” Materials. 2021. link Times cited: 10 Abstract: Amorphous/crystalline nanolaminate composites have aroused e… read more Abstract: Amorphous/crystalline nanolaminate composites have aroused extensive research interest because of their high strength and good plasticity. In this paper, the nanoindentation behavior of Cu64Zr36/Cu amorphous/crystalline nanolaminates (ACNLs) is investigated by molecular dynamics (MD) simulation while giving special attention to the plastic processes occurring at the interface. The load–displacement curves of ACNLs reveal small fluctuations associated with shear transformation zone (STZ) activation in the amorphous layer, whereas larger fluctuations associated with dislocations emission occur in the crystalline layer. During loading, local STZ activation occurs and the number of STZs increases as the indentation depth in the amorphous layer increases. These STZs are mostly located around the indenter, which correlates to the high stresses concentrated around the indenter. When the indenter penetrates the crystalline layer, dislocations emit from the interface of amorphous/crystalline, and their number increases with increasing indentation depth. During unloading, the overall number of STZs and dislocations decreases, while other new STZs and dislocations become activated. These results are discussed in terms of stress distribution, residual stresses, indentation rate and indenter radius. read less S. Zhang, W. Wang, and P. Guan, “Dynamic Crossover in Metallic Glass Nanoparticles,” Chinese Physics Letters. 2021. link Times cited: 3 X. Zhou, L. Wang, and C. Chen, “Atomistic investigation of mechanical properties of metallic glass nanocomposites,” Modelling and Simulation in Materials Science and Engineering. 2020. link Times cited: 1 Abstract: In this paper, tensile deformation of metallic glass (MG) na… read more Abstract: In this paper, tensile deformation of metallic glass (MG) nanocomposites which consist of cellular MG matrix and columnar grains are studied by the molecular dynamic simulations. The size effects of the ligament thickness and the grain size on the yield strength and plasticity are elucidated. It is found that the ratio of the grain size to the ligament thickness (d/s) has a great influence on the plastic deformation. Two typical deformation mechanisms are further investigated. In the composite models with large d/s, grain boundaries motion and voids formation are the main mechanisms. When d/s decreases to 6, the grains can not only promote multiple shear bands formation but also impede the main shear band propagation. As a result, large plastic plateau appears in the stress–strain curve. These results are helpful to optimize the mechanical properties of MG composites. read less J. Ma, H. Y. Song, J. Y. Wang, J. Dai, and Y. L. Li, “Influence of composition on the mechanical properties of metallic nanoglasses: Insights from molecular dynamics simulation,” Journal of Applied Physics. 2020. link Times cited: 3 Abstract: The introduction of a glass–glass interface is an effective … read more Abstract: The introduction of a glass–glass interface is an effective way to improve the plasticity of metallic glass. However, the strength–plasticity trade-off has not still been effectively overcome. Here, the effect of the composition on the mechanical properties and deformation behavior of the CuZr nanoglass (NG) is investigated under tensile loading by a molecular dynamics simulation. The results indicate that high-performance NGs can be obtained by adjusting the percentage of Cu atoms. There is a critical Cu content (i.e., 75%), which makes the NGs have both high strength and high plasticity. The results show that with the increase in the Cu content, the deformation mechanism of the NGs changes from necking to uniform plastic deformation and then to the nucleation and the growth of the main shear band. Our results underscore the importance of the composition in the design and preparation of high-performance metallic glass. read less G. Mahmud, H. Zhang, and J. Douglas, “Localization model description of the interfacial dynamics of crystalline Cu and Cu64Zr36 metallic glass films.,” The Journal of chemical physics. 2020. link Times cited: 7 Abstract: Recent studies of structural relaxation in Cu-Zr metallic gl… read more Abstract: Recent studies of structural relaxation in Cu-Zr metallic glass materials having a range of compositions and over a wide range of temperatures and in crystalline UO2 under superionic conditions have indicated that the localization model (LM) can predict the structural relaxation time τα of these materials from the intermediate scattering function without any free parameters from the particle mean square displacement ⟨r2⟩ at a caging time on the order of ps, i.e., the "Debye-Waller factor" (DWF). In the present work, we test whether this remarkable relation between the "fast" picosecond dynamics and the rate of structural relaxation τα in these model amorphous and crystalline materials can be extended to the prediction of the local interfacial dynamics of model amorphous and crystalline films. Specifically, we simulate the free-standing amorphous Cu64Zr36 and crystalline Cu films and find that the LM provides an excellent parameter-free prediction for τα of the interfacial region. We also show that the Tammann temperature, defining the initial formation of a mobile interfacial layer, can be estimated precisely for both crystalline and glass-forming solid materials from the condition that the DWFs of the interfacial region and the material interior coincide. read less X. Bian et al., “Signature of local stress states in the deformation behavior of metallic glasses,” NPG Asia Materials. 2020. link Times cited: 33 W. Wu, D. Şopu, X. Yuan, and J. Eckert, “Aspect ratio-dependent nanoindentation behavior of Cu64Zr36 metallic glass nanopillars investigated by molecular dynamics simulations,” Journal of Applied Physics. 2020. link Times cited: 8 Abstract: In this paper, we study nanoindentation in Cu64Zr36 metallic… read more Abstract: In this paper, we study nanoindentation in Cu64Zr36 metallic glass (MG) nanopillars with different aspect ratios by molecular dynamics simulations. The activation of shear transformation zones (STZs) and the deformation behavior of MG pillars are discussed during nanoindentation loading and unloading processes. Buckling and serrated flow are the two types of deformation behaviors observed during nanoindentation. For large aspect ratio pillars, a sudden stress drop in the load–displacement curve is found that relates to the buckling process, while smaller aspect ratio pillars exhibit large stress fluctuations. The serrated flow is associated with STZ activation. STZs are locally activated, and their number gradually increases with increasing indentation depth during loading, whereas their number decreases during unloading. For pillars with a large aspect ratio, no new STZs are activated and their number decreases rapidly once the indenter has left the sample because of the buckling deformation. In contrast, new STZs are activated for pillars with smaller aspect ratio during the unloading process. Analysis of STZ activation and shear localization reveals an inhomogeneous deformation process and an increase in the degree of structural heterogeneity as the aspect ratio of the pillars increases for both loading and unloading stages. The present work provides an insight into the atomic-scale plastic deformation behavior of MG nanopillars during nanoindentation loading and unloading processes. read less Z. Wu and R. Li, “Revisiting the breakdown of Stokes-Einstein relation in glass-forming liquids with machine learning,” Science China Physics, Mechanics & Astronomy. 2020. link Times cited: 3 K. E. Avila, S. Küchemann, I. A. Alhafez, and H. Urbassek, “An atomistic study of shear-band formation during cutting of metallic glasses,” Journal of Applied Physics. 2020. link Times cited: 17 Abstract: Using molecular dynamics simulations, we study the generatio… read more Abstract: Using molecular dynamics simulations, we study the generation of plasticity during cutting of a CuZr metallic glass. We characterize the deformation occurring at different cutting depths and velocities. A regular pattern of parallel shear bands forms in the chip in agreement with experimental work. The shear bands are better defined and further spaced apart for deeper cuts. For small cutting velocities ≤ 20 m / s, a sharp boundary plane separates the plastically deformed material in the chip from the virgin workpiece. This is the case even for the deepest cuts performed. The chip is of roughly prismatic shape; its thickness is determined by how fast the shear bands formed within the chip propagate. We find that at the core of a shear band, the number of full icosahedral clusters decreases by more than 50%. At higher cut velocities, we find bent shear bands and irregular shear-band patterns when shear bands merge. read less C. Wu and R.-E. Li, “Effects of alloy composition, cavity aspect ratio, and temperature of imprinted ZrCu metallic glass films: a molecular dynamics study,” Applied Physics A. 2020. link Times cited: 7 C. Wu and R.-E. Li, “Effects of alloy composition, cavity aspect ratio, and temperature of imprinted ZrCu metallic glass films: a molecular dynamics study,” Applied Physics A. 2020. link Times cited: 0 M.-fei Li, B. Liao, Y. Wang, and L. Yang, “Structural mechanisms of the high glass-forming ability in CuZrTiPd metallic glass,” Journal of Materials Science. 2019. link Times cited: 3 Z. Chen et al., “Chiral metallic glass nanolattices with combined lower density and improved auxeticity.,” Physical chemistry chemical physics : PCCP. 2019. link Times cited: 6 Abstract: Auxetic materials are promising structural and functional ca… read more Abstract: Auxetic materials are promising structural and functional candidates due to their unique lateral expansion when stretched, however, bulk metallic glasses (MGs) could not show any auxeticity because of their intrinsic isotropic nature. Here we construct chiral Cu50Zr50 metallic glass nanolattices with cavities, and investigate their auxeticity and underlying mechanism with molecular dynamics simulations. It is found that, compared to monolithic MGs, all the chiral metallic glass nanolattices (CMGNs) exhibit improved auxeticity and lower density. For CMGNs with cavities, the negative Poisson's ratio and ultimate tensile strength (UTS) increase first and then decrease with increasing cavity radius, with the cavity radius of 2.5 nm being the most favorable for auxeticity and enhanced UTS. The auxetic mechanism is attributed to the competition between rotation behavior and non-affine deformation under tension. Our study not only reveals the mechanism of auxeticity in CMGNs having cavities but also provides a feasible method to optimize their auxetic performance and density by structure designing of MGs. read less K. E. Avila, S. Kuchemann, and H. Urbassek, “Stucture and size of the plastic zone formed during nanoindentation of a metallic glass,” Journal of Non-Crystalline Solids. 2019. link Times cited: 9 K. E. Avila, S. Kuchemann, I. A. Alhafez, and H. Urbassek, “Nanoscratching of metallic glasses – An atomistic study,” Tribology International. 2019. link Times cited: 42 Q. Zhang, Q. Li, S. Zhao, W. Wang, and M. Li, “Structural characteristics in deformation mechanism transformation in nanoscale metallic glasses,” Journal of Physics: Condensed Matter. 2019. link Times cited: 1 Abstract: Deformation of metallic glasses is closely related to their … read more Abstract: Deformation of metallic glasses is closely related to their microstructures which depend on the composition, processing method, and the size of the materials. This subtle structure-property relation is fairly complex and remains to be explored. Here, we scrutinize the microstructural evolution in relation to the mechanical properties in metallic glass nanowires with the same composition and size but subtle microstructural differences by controlling the preparing process using molecular dynamics simulations. The results suggest that a structural threshold exists for the transformation of deformation mechanisms in metallic glasses: when the structural feature exceeds the threshold, the deformation changes from homogeneous flow to shear localized deformation. read less Y. Zhang et al., “Atomic-level crystallization in selective laser melting fabricated Zr-based metallic glasses.,” Physical chemistry chemical physics : PCCP. 2019. link Times cited: 16 Abstract: As a promising additive manufacturing technique, selective l… read more Abstract: As a promising additive manufacturing technique, selective laser melting (SLM) provides the possibility of fabricating metallic glassy components free of the constraints of geometrical complexity and dimensions. However, unexpected crystallization greatly affects the microstructure and degrades the mechanical performance of SLM-fabricated metallic glasses (MGs). To clarify the crystallization mechanism and the effect of laser processing on the crystallization, we investigate the atomic-level crystallization in the SLM Zr90Cu10 MG by using molecular dynamics simulations. The results show that crystallization highly related to scan speed lies in the atomic-level cluster changes. Lower scan speed leads to a dramatically increased fraction of the BCC crystal phase, accompanied by the nucleation of a few HCP and FCC crystal phases. As scan speed increases, more icosahedron-like clusters are formed, leading to the formation of the MG, while the nucleation of the crystal phase is suppressed. The suppression of crystallization is further attributed to a higher average temperature variation rate induced by higher scan speed, which reduces the relaxation time, preventing the nucleation and growth of crystal phases. This work contributes to the understanding of the crystallization in MGs during the SLM process at the atomic level, providing guidance to suppress the crystallization in the SLM process of desired metallic glassy components. read less B. Cheng and J. Trelewicz, “Interfacial plasticity governs strain delocalization in metallic nanoglasses,” Journal of Materials Research. 2019. link Times cited: 12 Abstract: Intrinsic size effects in nanoglass plasticity have been con… read more Abstract: Intrinsic size effects in nanoglass plasticity have been connected to the structural length scales imposed by the interfacial network, and control over this behavior is critical to designing amorphous alloys with improved mechanical response. In this paper, atomistic simulations are employed to probe strain delocalization in nanoglasses with explicit correlation to the interfacial characteristics and length scales of the amorphous grain structure. We show that strength is independent of grain size under certain conditions, but scales with the excess free volume and degree of short-range ordering in the interfaces. Structural homogenization upon annealing of the nanoglasses increases their strength toward the value of the bulk metallic glass; however, continued partitioning of strain to the interfacial regions inhibits the formation of a primary shear band. Intrinsic size effects in nanoglass plasticity thus originate from biased plastic strain accumulation within the interfacial regions, which will ultimately govern strain delocalization and homogenous flow in nanoglasses. read less F. Chen and D. Xu, “3D surface condensation of large atomic shear strain in nanoscale metallic glasses under low uniaxial stress,” Journal of Physics: Condensed Matter. 2018. link Times cited: 1 Abstract: Nanoscale metallic glasses (MGs) are frequently used in expe… read more Abstract: Nanoscale metallic glasses (MGs) are frequently used in experimental and computational studies to probe the deformation mechanisms in amorphous metals. Potential consequences of the significant surface to volume ratio in these extremely small materials, nevertheless, are not well understood. Here, using molecular dynamics simulations and novel selective 3D visualization, we show that significant irreversible atomic shear strain condenses on the 3D surface of these materials under low uniaxial stress, while the interior atoms are bearing much lower, mostly reversible shear strain. This is observed for various sample geometries, dimensions, strain rates and temperatures, and attributable to the correlations of atomic shear strain with atomic potential energy and coordination number. The results reveal the profound influence of the surface on the strain partitioning in nanoscale MGs across the 3D volume, critical to the initiation and continuation of plasticity. read less Z. Ling, X. Huang, and L. Dai, “Probe Embryonic Damage Evolution in Bulk Metallic Glasses under Plate-impact Loading.” 2018. link Times cited: 1 Abstract: Microdamage in very short stress durations of spallation pro… read more Abstract: Microdamage in very short stress durations of spallation process in Zr-based bulk metallic glass (Zr-BMG) samples were captured by a specially designed plate impact technique. With stress durations vary, microdamage “frozen” in Zr-BMG samples exhibited different damage levels. Based on the morphology and stress environment of the microdamage, a compound microdamage evolution mode is applied to characterize the spallation evolution in Zr-BMGs. Especially the spallation in BMGs originates from cavitation instabilities in the weak regions with higher free volume content, which results in formation of ductile damage zones. The activation of shear transformation zones (STZs) or tension transformation zones (TTZs) between these ductile damage zones finally leads to detached spallation. read less Z. Wu, W. Kob, W.-H. Wang, and L. Xu, “Stretched and compressed exponentials in the relaxation dynamics of a metallic glass-forming melt,” Nature Communications. 2018. link Times cited: 47 S. Scudino et al., “Ductile bulk metallic glass by controlling structural heterogeneities,” Scientific Reports. 2018. link Times cited: 42 B. Demaske, S. Phillpot, and D. Spearot, “Atomic-level deformation of CuxZr100-x metallic glasses under shock loading,” Journal of Applied Physics. 2018. link Times cited: 18 Abstract: Plastic deformation mechanisms in CuxZr100-x bulk metallic g… read more Abstract: Plastic deformation mechanisms in CuxZr100-x bulk metallic glasses (MGs) subjected to shock are investigated using molecular dynamics simulations. MGs with Cu compositions between 30 and 70 at. % subjected to shock waves generated via piston velocities that range from 0.125 to 2.0 km/s are considered. In agreement with prior studies, plastic deformation is initiated via formation of localized regions of high von Mises shear strain, known as shear transformation zones (STZs). At low impact velocities, but above the Hugoniot elastic limit, STZ nucleation is dispersed behind the shock front. As impact velocity is increased, STZ nucleation becomes more homogeneous, eventually leading to shock-induced melting, which is identified in this work via high atomic diffusivity. The shear stress necessary to initiate plastic deformation within the shock front is independent of composition at shock intensities near the elastic limit but increases with increasing Cu content at high shock intensities. By contrast, both the flow stress in the plastically deformed MG and the critical shock pressure associated with melting behind the shock front are found to increase with increasing Cu content over the entire range of impact velocities. The evolution of the short-range order in the MG samples during shock wave propagation is analyzed using a polydisperse Voronoi tessellation method. Cu-centered polyhedra with full icosahedral symmetry are found to be most resistant to change under shock loading independent of the MG composition. A saturation is observed in the involvement of select Cu-centered polyhedra in the plastic deformation processes at a piston velocity around 0.75 km/s.Plastic deformation mechanisms in CuxZr100-x bulk metallic glasses (MGs) subjected to shock are investigated using molecular dynamics simulations. MGs with Cu compositions between 30 and 70 at. % subjected to shock waves generated via piston velocities that range from 0.125 to 2.0 km/s are considered. In agreement with prior studies, plastic deformation is initiated via formation of localized regions of high von Mises shear strain, known as shear transformation zones (STZs). At low impact velocities, but above the Hugoniot elastic limit, STZ nucleation is dispersed behind the shock front. As impact velocity is increased, STZ nucleation becomes more homogeneous, eventually leading to shock-induced melting, which is identified in this work via high atomic diffusivity. The shear stress necessary to initiate plastic deformation within the shock front is independent of composition at shock intensities near the elastic limit but increases with increasing Cu content at high shock intensities. By contrast, both t... read less Y. F. Wang, H. Y. Li, and L. Yang, “Radiation-induced structural evolution in Zr2Cu metallic glass,” Journal of Materials Science. 2018. link Times cited: 17 P. Wen, B. Demaske, D. Spearot, and S. Phillpot, “Shock compression of CuxZr100−x metallic glasses from molecular dynamics simulations,” Journal of Materials Science. 2018. link Times cited: 21 L. Yang et al., “Structural responses of metallic glasses under neutron irradiation,” Scientific Reports. 2017. link Times cited: 27 B. Liao, S.-yang Wu, and L. Yang, “Free volume: An indicator of the glass-forming ability in binary alloys,” AIP Advances. 2017. link Times cited: 6 Abstract: As a specific concept, free volume is proposed to affect the… read more Abstract: As a specific concept, free volume is proposed to affect the glass formation in alloys, while such issue remains unsolved, because free volume itself is ambiguous and elusive. In this work, the correlation between the free volume and the glass-forming ability (GFA) in some binary alloy systems has been investigated by a series of simulations combined with synchrotron-radiation based experiments. A new approach for detecting void spaces and even free volumes quantitatively in metallic glasses is developed, based on which we reveal that the size of free volumes significantly affects the glass formation. In particular, for ribbons with different compositions but the same thickness, a composition where there is a local maximum of GFA, there is a local bump of size value of free volumes, making it possible for free volumes to be an effective indicator of GFA. The present work provides new insight into the glass formation from free volume aspect, which can be helpful for understanding of both structure and prop... read less X. Zhao, C. Wang, H. Zheng, Z.-an Tian, and L. Hu, “The role of liquid-liquid transition in glass formation of CuZr alloys.,” Physical chemistry chemical physics : PCCP. 2017. link Times cited: 37 Abstract: Some glass-forming liquids have different liquid phases that… read more Abstract: Some glass-forming liquids have different liquid phases that have the same composition but different structure, density and entropy. Based on experimental and molecular dynamics simulation, we here report thermodynamic, dynamic, and structural evidence of the liquid-liquid transition (LLT) in ten Cu-Zr glass-forming liquids well above the liquidus temperature. We find that for Cu-Zr alloys, the LLT is beneficial to glass formation, and there is a close relationship between the relative transition strength (RTS) of the LLT and the critical thickness representing the glass forming ability (GFA): the bigger the value of the RTS parameters, the stronger the GFA of Cu-Zr alloys. This work not only uncovers the role of the LLT of melts in the glass formation of solids, but also sheds light on the inheritance of properties of glassy solids from the aspect of the detectable dynamics of high-temperature melts. read less W. Jian, L. Wang, B. Li, X. Yao, and S. Luo, “Improved ductility of Cu64Zr36 metallic glass/Cu nanocomposites via phase and grain boundaries,” Nanotechnology. 2016. link Times cited: 27 Abstract: We investigate tensile deformation of metallic glass/crystal… read more Abstract: We investigate tensile deformation of metallic glass/crystalline interpenetrating phase nanocomposites as regards the effects of specific area of amorphous/crystalline phase interfaces, and grain boundaries. As an illustrative case, large-scale molecular dynamics simulations are performed on Cu64Zr36 metallic glass/Cu nanocomposites with different specific interface areas and grain boundary characteristics. Plastic deformation is achieved via shear bands, shear transformation zones, and crystal plasticity. Three-dimensional amorphous/crystalline interfaces serve as effective barriers to the propagation of shear transformation zones and shear bands if formed, diffuse strain localizations, and give rise to improved ductility. Ductility increases with increasing specific interface area. In addition, introducing grain boundaries into the second phase facilitates crystal plasticity, which helps reduce or eliminate mature shear bands in the glass matrix. read less W. Jian, X. Yao, L. Wang, X. C. Tang, and S. Luo, “Short- and medium-range orders in Cu46Zr54 metallic glasses under shock compression,” Journal of Applied Physics. 2015. link Times cited: 26 Abstract: We investigate short- and medium-range orders in Cu46Zr54 me… read more Abstract: We investigate short- and medium-range orders in Cu46Zr54 metallic glasses, as represented by icosahedra and icosahedron networks, respectively, under shock compression with molecular dynamics simulations. Complementary isothermal compression and isobaric heating simulations reveal that compression below 60 GPa gives rise to increased coordination and thus high-coordination-number Voronoi polyhedra, such as icosahedra; however, pressure-induced collapse or thermal disintegration of icosahedra (and subsequently, icosahedron networks) occurs at pressures above 60 GPa or at melting, accompanied by free volume increase. The evolutions of the short- and medium-range orders upon shock loading are the effects of compression combined with shock-induced melting. The structural changes are partially reversible for weak shocks without melting (below 60 GPa) and irreversible for strong shocks. Crystallization does not occur under isothermal or shock compression at molecular dynamics scales. read less Q. Zhang, Q. Li, and M. Li, “Internal stress and its effect on mechanical strength of metallic glass nanowires,” Acta Materialia. 2015. link Times cited: 20 D. Şopu and K. Albe, “Influence of grain size and composition, topology and excess free volume on the deformation behavior of Cu–Zr nanoglasses,” Beilstein Journal of Nanotechnology. 2015. link Times cited: 44 Abstract: The influence of grain size and composition on the mechanica… read more Abstract: The influence of grain size and composition on the mechanical properties of Cu–Zr nanoglasses (NGs) is investigated by molecular dynamics simulations using two model glasses of different alloy composition, namely Cu64Zr36 (Cu-rich) and Cu36Zr64 (Zr-rich). When the grain size is increased, or the fraction of interfaces in these NGs is decreased, we find a transition from a homogeneous to an inhomogeneous plastic deformation, because the softer interfaces are promoting the formation shear transformation zones. In case of the Cu-rich system, shear localization at the interfaces is most pronounced, since both the topological order and free volume content of the interfaces are very different from the bulk phase. After thermal treatment the redistribution of free volume leads to a more homogenous deformation behavior. The deformation behavior of the softer Zr-rich nanoglass, in contrast, is only weakly affected by the presence of glass–glass interfaces, since the interfaces don’t show topological disorder. Our results provide clear evidence that the mechanical properties of metallic NGs can be systematically tuned by controlling the size and the chemical composition of the glassy nanograins. read less X. Huang, Z. Ling, and L. Dai, “Ductile-to-brittle transition in spallation of metallic glasses,” Journal of Applied Physics. 2014. link Times cited: 29 Abstract: In this paper, the spallation behavior of a binary metallic … read more Abstract: In this paper, the spallation behavior of a binary metallic glass Cu50Zr50 is investigated with molecular dynamics simulations. With increasing the impact velocity, micro-voids induced by tensile pulses become smaller and more concentrated. The phenomenon suggests a ductile-to-brittle transition during the spallation process. Further investigation indicates that the transition is controlled by the interaction between void nucleation and growth, which can be regarded as a competition between tension transformation zones (TTZs) and shear transformation zones (STZs) at atomic scale. As impact velocities become higher, the stress amplitude and temperature rise in the spall region increase and micro-structures of the material become more unstable. Therefore, TTZs are prone to activation in metallic glasses, leading to a brittle behavior during the spallation process. (C) 2014 AIP Publishing LLC. read less S. Chill et al., “EON: software for long time simulations of atomic scale systems,” Modelling and Simulation in Materials Science and Engineering. 2014. link Times cited: 56 Abstract: The EON software is designed for simulations of the state-to… read more Abstract: The EON software is designed for simulations of the state-to-state evolution of atomic scale systems over timescales greatly exceeding that of direct classical dynamics. States are defined as collections of atomic configurations from which a minimization of the potential energy gives the same inherent structure. The time evolution is assumed to be governed by rare events, where transitions between states are uncorrelated and infrequent compared with the timescale of atomic vibrations. Several methods for calculating the state-to-state evolution have been implemented in EON, including parallel replica dynamics, hyperdynamics and adaptive kinetic Monte Carlo. Global optimization methods, including simulated annealing, basin hopping and minima hopping are also implemented. The software has a client/server architecture where the computationally intensive evaluations of the interatomic interactions are calculated on the client-side and the state-to-state evolution is managed by the server. The client supports optimization for different computer architectures to maximize computational efficiency. The server is written in Python so that developers have access to the high-level functionality without delving into the computationally intensive components. Communication between the server and clients is abstracted so that calculations can be deployed on a single machine, clusters using a queuing system, large parallel computers using a message passing interface, or within a distributed computing environment. A generic interface to the evaluation of the interatomic interactions is defined so that empirical potentials, such as in LAMMPS, and density functional theory as implemented in VASP and GPAW can be used interchangeably. Examples are given to demonstrate the range of systems that can be modeled, including surface diffusion and island ripening of adsorbed atoms on metal surfaces, molecular diffusion on the surface of ice and global structural optimization of nanoparticles. read less Y. Zhang, N. Mattern, and J. Eckert, “Strong correlation of atomic thermal motion in the first coordination shell of a Cu-Zr metallic glass,” Applied Physics Letters. 2013. link Times cited: 8 Abstract: We demonstrate a strong correlation of atomic thermal motion… read more Abstract: We demonstrate a strong correlation of atomic thermal motions in the first coordination shell of Cu50Zr50 metallic glass using molecular dynamics simulations, which explains directly the small thermal expansion coefficient calculated by the first maxima of pair correlation functions. The vibrational anisotropy in the glass is found to be even higher than in crystalline copper. The parallel-perpendicular anisotropy gradually decreases upon heating. The anisotropy in Zr–Zr is the strongest bonds among all the interatomic bonds, which is also very stable near the glass transition at 700 K. Structurally, the anisotropy can be correlated to Cu-centered (0 2 8 1) clusters. read less Z. W. Wu, M. Li, W.-Q. Wang, W. Song, and K. Liu, “Effect of local structures on structural evolution during crystallization in undercooled metallic glass-forming liquids.,” The Journal of chemical physics. 2013. link Times cited: 18 Abstract: The effect of local structures on structural evolution durin… read more Abstract: The effect of local structures on structural evolution during the crystallization of undercooled ZrCu metallic glass-forming liquid was studied via molecular dynamics simulations. It is found that body-centered-cubic (bcc)-like clusters play a key role in structural evolution during crystallization. In contrast to previous speculations, the number of bcc-like crystal nuclei does not change much before the onset of crystallization. Instead, the development of a bcc-like critical nucleus during annealing leads to a strong spatial correlation with other nuclei in its surroundings, forming a crystalline structure template. It is also found that the size distribution of bcc-like nuclei follows a power-law form with an exponential cutoff in the early stage of annealing, but changes to a pure power-law behavior just before the onset of crystallization. This implies that the crystalline structure template has fractal feature and the undercooled liquids evolve to a self-organized critical state before the onset of crystallization, which might trigger the subsequent rapid crystallization. According to the graph theory analysis, it is also found that the observed large scatter of the onset time of crystallization in different liquid samples results from the connectivity of the bcc-like clusters. read less Y. Ritter and K. Albe, “Chemical and topological order in shear bands of Cu64Zr36 and Cu36Zr64 glasses,” Journal of Applied Physics. 2012. link Times cited: 43 Abstract: Shear bands in binary Cu64Zr36 and Cu36Zr64 metallic glasses… read more Abstract: Shear bands in binary Cu64Zr36 and Cu36Zr64 metallic glasses are studied by molecular dynamics simulations with respect to their chemical and topological short range order. In both glasses, shear band formation goes along with an increase in excess volume inside the shear band. Only in the Cu-rich alloy, where Cu-centered icosahedra represent the most abundant topological unit, the dilatation within the shear band is related to a decrease in the number of icosahedral units, while the degree of cross-linking and the cluster size decrease when a shear band forms. In the Cu36Zr64 glass, in contrast, no topological feature changes when the material starts yielding and a shear band is formed. The chemical short range order, however, is affected in both materials within the shear band, which is revealed by an increase in the number of Cu–Cu and Zr–Zr bonds. Since all structural modifications are rather the result of plastic deformation than a pre-requisite, we conclude that the presence of distinct topological features, such as icosahedral units, is not a pre-requisite for shear band formation. read less P. Murali, Y. W. Zhang, and H. Gao, “On the characteristic length scales associated with plastic deformation in metallic glasses,” Applied Physics Letters. 2012. link Times cited: 21 Abstract: Atomistic simulations revealed that the spatial correlations… read more Abstract: Atomistic simulations revealed that the spatial correlations of plastic displacements in three metallic glasses, FeP, MgAl, and CuZr, follow an exponential law with a characteristic length scale lc that governs Poisson’s ratio ν, shear band thickness tSB, and fracture mode in these materials. Among the three glasses, FeP exhibits smallest lc, thinnest tSB, lowest ν, and brittle fracture; CuZr exhibits largest lc, thickest tSB, highest ν, and ductile fracture, while properties of MgAl lie in between those of FeP and CuZr. These findings corroborate well with existing experimental observations and suggest lc as a fundamental measure of the shear transformation zone size in metallic glasses. read less K. N. Lad, N. Jakse, and A. Pasturel, “Signatures of fragile-to-strong transition in a binary metallic glass-forming liquid.,” The Journal of chemical physics. 2012. link Times cited: 82 Abstract: Classical molecular dynamics investigations of the evolution… read more Abstract: Classical molecular dynamics investigations of the evolution of the microscopic structure and atomic dynamics are found to provide signatures of fragile-to-strong transition in a Cu-Zr bulk metallic glass forming alloy. Present study reveals that (i) the alloy exhibits a non-monotonic decoupling of the self-diffusion coefficient D and the relaxation time τ as observed in case of supercooled water despite the difference in the intermolecular interactions compared to this system, (ii) the temperature dependence of D and τ suggests a crossover from non-Arrhenius to Arrhenius behavior near mode-coupling transition temperature T(C), and (iii) the alloy exhibits a crossover from Stokes-Einstein ((D ~ (τ/T)(-1)) to fractional Stokes-Einstein (D ∝ (τ/T)(-ζ)) with exponent ζ ≈ 0.6. A weak first-order transition, associated with the fragile-to-strong transition, has also been observed in the undercooled region. These findings are in accordance with the growing idea of fragile-to-strong crossover having larger generality than the traditional classification of the glass-forming liquids as fragile and strong. read less H. Peng, M. Li, W. Wang, C. Wang, and K. Ho, “Effect of local structures and atomic packing on glass forming ability in CuxZr100−x metallic glasses,” Applied Physics Letters. 2010. link Times cited: 174 Abstract: Molecular dynamics simulations are performed for CuZr metall… read more Abstract: Molecular dynamics simulations are performed for CuZr metallic alloys to study the structural and dynamical features for glass forming ability (GFA). Our analysis shows that in CuZr metallic system, although ⟨0,0,12,0⟩ icosahedral clusters are important, some Zr-centered clusters such as ⟨0,1,10,4⟩ and ⟨0,1,10,5⟩ play a key role in slowing down the dynamics. It is found that these Zr-centered clusters are intrinsically slow and fundamentally determine the stability and slow dynamics. Due to the strong spatial correlation between ⟨0,0,12,0⟩ and Zr-centered clusters, their relative population influences the dense packing and dynamics in metallic glasses, and further the GFA. read less Y. Sun, J. Shen, and A. A. Valladares, “Atomic structure and diffusion in Cu60Zr40 metallic liquid and glass: molecular dynamics simulations,” Journal of Applied Physics. 2009. link Times cited: 33 Abstract: Temperature effects on the structural evolution and diffusiv… read more Abstract: Temperature effects on the structural evolution and diffusivity of Cu60Zr40 in the liquid and glassy states were studied by molecular dynamics simulations using the Finnis–Sinclair potential. The pair distribution functions and common-neighbor analysis were used to investigate the structural variations. It is found that the amount of pentagonal bipyramids increases sharply in a short temperature range of about 200 K above the glass transition temperature Tg, leading to the increasing of the icosahedral cluster centered by Cu atom and larger Kasper polyhedral cluster centered by Zr atom. The mean square displacement and the self part of the van Hove function were calculated to evaluate the relaxation and transport properties. The cage effect is found to appear at 1100 K. The mode-coupling theory equation is more suitable than the Vogel–Fulcher–Tammann equation to describe the change in diffusivity in the liquid state. The critical temperature Tc, a predicted glass transition temperature in mode-coupling th... read less V. K. Sutrakar and D. Mahapatra, “Comment on ‘Pseudoelasticity of Cu–Zr nanowires via stress-induced martensitic phase transformations’ [Appl. Phys. Lett. 95, 021911 (2009)],” Applied Physics Letters. 2009. link Times cited: 9 Abstract: Recently, a novel stress-induced phase transformation in an … read more Abstract: Recently, a novel stress-induced phase transformation in an initial ⟨100⟩/{100} B2-CuZr nanowire has been reported for the first time [Sutrakar and Mahapatra, Mater. Lett. 63, 1289 (2009)]. Following this, a martenisitic phase transformation in Cu–Zr nanowire was shown [Cheng et al., Appl. Phys. Lett. 95, 021911 (2009)] using the same idea [Sutrakar and Mahapatra, Mater. Lett. 63, 1289 (2009)]. The pseudoelastic recovery of the bct phase of Cu–Zr by unloading has also been shown [Cheng et al., Appl. Phys. Lett. 95, 021911 (2009)]. They also tested the epitaxial bain path [Alippi et al., Phys. Rev. Lett. 78, 3892 (1997)] and reported that the bct phase in the nanowire is metastable, whereas the bulk counterpart is unstable. This aspect is re-examined in this comment with corrected results. read less D. Şopu, K. Albe, Y. Ritter, and H. Gleiter, “From nanoglasses to bulk massive glasses,” Applied Physics Letters. 2009. link Times cited: 78 Abstract: Molecular dynamics simulations are presented that provide ev… read more Abstract: Molecular dynamics simulations are presented that provide evidence for the existence of diluted interfaces in nanoglasses, which is a class of material that can be synthesized by consolidating glassy nanoparticles. By comparing simulations of a covalently bonded Ge nanoglass and a metallic CuZr nanoglass, we show that the delocalization of the excess free volume initially located within the interfaces depends on the flow strain of the material. Our results suggest that the density distribution within a nanoglass can be controlled by the initial particle size and the annealing conditions. Therefore, nanoglasses represent an alternative route for controlling the properties of glassy materials. read less M. Mendelev, R. Ott, M. Kramer, and D. Sordelet, “Determining strain in amorphous alloys: Uncertainties with analyzing structural changes during deformation,” Journal of Applied Physics. 2009. link Times cited: 1 Abstract: Molecular dynamics simulations were utilized to test the rel… read more Abstract: Molecular dynamics simulations were utilized to test the reliability of strain values obtained from diffraction data for noncrystalline alloys. We found that in the case of a one-component system, the strain value obtained from the pair correlation functions underestimates the actual value because of a small degree of atomic relaxations, which minimize the effects of the applied deformation. In the case of multicomponent systems, the different pairs are affected by applied deformation to different extents; moreover, this implies that the strain value determined from diffraction data should depend on the type of scattering. read less M. Mendelev, D. Rehbein, R. Ott, M. Kramer, and D. Sordelet, “Computer simulation and experimental study of elastic properties of amorphous Cu-Zr alloys,” Journal of Applied Physics. 2007. link Times cited: 57 Abstract: Molecular-dynamics simulations were performed to determine t… read more Abstract: Molecular-dynamics simulations were performed to determine the elastic constants of CuxZr100−x (33.3≤x≤64.5) metallic glasses at room temperature. The accuracy of the interatomic potentials used to obtain the model glass structures was tested by comparing to the total structure factors obtained from high-energy synchrotron x-ray diffraction and, more importantly, to acoustic velocities measured from melt spun ribbons. Both the simulated and measured acoustic velocities increased at comparable rates with increasing Cu concentration, but the former underestimated the latter by about 10%. Young’s moduli of the simulated models were determined by combining the ultrasonic data with densities that were obtained from simulations. In addition, the compositional dependence of Poisson’s ratio, shear modulus, and bulk modulus for this series of simulated metallic glasses was determined. Examination of partial-pair correlations deduced from simulated glass structures shows a correlation between higher bulk moduli in ... read less N. Fayzullayev, J. Kurbonov, L. U. Uktamov, R. J. Kurbonova, and J. Kurbonov, “The effect of reagents on the production of highly nanocomposite bentonite sorbents using zol-gel technology,” E3S Web of Conferences. 2023. link Times cited: 0 Abstract: In this study, the analysis of the study of the effect of re… read more Abstract: In this study, the analysis of the study of the effect of reagents upon receipt of cargo was highlighted—nanocomposite bentonite sorbents using Sol–gel technology and the results obtained were highlighted. The comparative surface surface was calculated at 77 K using a nitrogen adsorption isotherm. The size and pore size of the catalysts were determined from data on desorption and adsorption isotherms, respectively, at a relative pressure R/ro=0.99 in accordance with the BJH (Barette–Joyner–Halend) model. Bentonite in Navoi region of Navahor district is a light gray powder, odorless, practically insoluble in water and organic solvents, the pH value of the suspension is 7.1–8.7. The weak alkalinity of the suspension is explained by the presence of hydroxide soil and hydroxide metals in the clay. According to its adsorption properties, it is a combined meso–macromicrobial adsorbent, its specific surface area is 54.5 m2/g, the porosity volume is 0.065 cm3/g, the average porosity is 4.8 nm, the adsorption activity for blue methylene is 62.0 bentonite/g. read less A. Anggono et al., “Combined Effects of Annealing and Cyclic Loading on Structural Rejuvenation and Mechanical Properties of CuZr Metallic Glass: A Molecular Dynamics Study,” Materials Research. 2022. link Times cited: 3 Abstract: 2021 Structural rejuvenation is one of the key topics in the… read more Abstract: 2021 Structural rejuvenation is one of the key topics in the field of metallic glasses (MGs). In this work, we evaluated the combined effects of annealing treatment and elastic cyclic loading to discover pathways for promoting structural rejuvenation and improving the mechanical properties in the MGs. Using molecular dynamics (MD) simulations, it was revealed that the sole cyclic loading led to the increase of rejuvenation degree; however, a saturated state was observed upon the 40 th cycle. On the other side, the sample exposed to the combined treatment exhibited a slight relaxation at the first step of cycling process and then a sharp rejuvenation degree was detected in the material. The thorough analyses indicated that the change in the fraction of coordination polyhedrons at the relaxation stage was the main reason for the extra rejuvenation in the sample exposed to the combined treatments. The results also suggest that the combination of rejuvenation treatments improves the magnitude of rejuvenation in the amorphous alloys. It should be noted that the increase of rejuvenation in the alloying systems accompanied with a reduction in the tensile strength and an enhancement in the homogenous plastic read less Y.-chen Cui, Y. Shibutani, P. Huang, F. Wang, K. Xu, and T. Lu, “Interface-Related Shear Banding Deformation of Amorphous/Crystalline CuZr/Cu Nanolaminates by Molecular Dynamics Simulations,” Materials Transactions. 2017. link Times cited: 1 Abstract: 1State-key Laboratory for Mechanical Behavior of Material, X… read more Abstract: 1State-key Laboratory for Mechanical Behavior of Material, Xi’an Jiaotong University, Xi’an 710049, China 2Department of Mechanical Engineering, Osaka University, Osaka, Japan 3State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi’an Jiaotong University, Xi’an 710049, China 4MOE Key Laboratory for Multifunctional Materials and Structures, Xi’an Jiaotong University, Xi’an 710049, China read less L. Dai, X. Huang, and Z. Ling, “Cavitation instability in bulk metallic glasses.” 2015. link Times cited: 0 Abstract: Recent experiments have shown that fracture surfaces of hulk… read more Abstract: Recent experiments have shown that fracture surfaces of hulk metallic glasses (BMGs) usually exhibit an intriguing nanoscale corrugation like fractographic feature mediated by nanoscale void formation. We attribute the onset of this nanoscale corrugation to TTZs (tension transformation zones) mediated cavitation. In our recent study, the spall experiments of Zr-based BMG using a single-stage light gas gun were performed. To uncover the mechanisms of the spallation damage nucleation and evolution, the samples were designed to be subjected to dynamic tensile loadings of identical amplitude but with different durations by making use of the multi-stress pulse and the double-flyer techniques. It is clearly revealed that the macroscopic spall fracture in BMGs originates from the nucleation, growth and coalescence of micro-voids. Then, a microvoid nucleation model of BMGs based on free volume theory is proposed, which indicates that the nucleation of microvoids at the early stage of spallation in BMGs is resulted from diffusion and coalescence of free volume. Furthermore, a theoretical model of void growth in BMGs undergoing remote dynamic hydrostatic tension is developed. The critical condition of cavitation instability is obtained. It is found that dynamic void growth in BMGs can he well controlled by a dimensionless inertial number characterizing the competition between intrinsic and extrinsic time scales. To unveil the atomic-level mechanism of cavitation, a systematic molecular dynamics (MD) simulation of spallation behaviour of a binary metallic glass with different impact velocities was performed. It is-found that micro-void nucleation is determined TTZs while the growth is controlled by shear transformation zones (STZs) at atomic scale. read less S. Biwa, S. Kishiwada, C. Inserra, and E. Matsumoto, “Modeling of Flexural Wave Propagation in a Plate with Contacting Interfaces,” Journal of Solid Mechanics and Materials Engineering. 2010. link Times cited: 5 Abstract: Propagation characteristics of a flexural wave in a thin pla… read more Abstract: Propagation characteristics of a flexural wave in a thin plate which surfaces are in imperfect contact with solid bodies are examined theoretically as well as numerically. To this purpose, a nonlinear interface model of solid-solid contact is incorporated in the Mindlin plate theory. The governing differential equations are derived for a plate in contact with rigid bodies on both surfaces, and the dispersion relation for infinitesimal amplitudes is obtained theoretically. The derived equations are solved by the finite difference method to examine the propagation of a flexural wave packet. The numerical results show that the interfacial stiffnesses influence the velocity and the broadening of the propagating wave packet, and the contact nonlinearity brings about harmonic generation. It is discussed how these features are influenced by the linear and nonlinear interface parameters, the wave amplitude and the propagation distance. read less A. Agrawal, S. Bakhtiari, R. Mirzaeifar, D. Jiang, H. Yang, and Y. Liu, “A comparative study of the amorphization of NiTi-B2 structure by anti-site defects,” Journal of Alloys and Compounds. 2024. link Times cited: 0 W. Song, Y. Meng, L. Xiao, and S. Liu, “Tuning dynamic mechanical properties of Cu50Zr50 nanoglasses/ nanopolycrystalline Cu composites investigated by molecular dynamics simulation,” Journal of Non-Crystalline Solids. 2024. link Times cited: 0 H. Ma et al., “Roots seeking of multiple shear-bands in amorphous alloys at the atomic scale,” Journal of Non-Crystalline Solids. 2024. link Times cited: 0 X. Fu et al., “The innate interfacial elastic strain field of a transformable B2 precipitate embedded in an amorphous matrix,” npj Computational Materials. 2023. link Times cited: 0 Y. Luo, J. Huang, X. Yu, G. Liu, S. Cao, and D. Fan, “The effect of crystalline structure on the mechanical behavior in Zr-based amorphous materials: A molecular dynamics simulation,” Journal of Non-Crystalline Solids. 2023. link Times cited: 0 K. E. Avila, V. Vardanyan, T. Zhu, S. Küchemann, M. Smaga, and H. Urbassek, “Plasticity in cyclic indentation of a Cu-Zr-based bulk metallic glass after tensile loading: An experimental and molecular dynamics simulation study,” Journal of Non-Crystalline Solids. 2023. link Times cited: 1 Z. Zhou et al., “Effect of precipitate shape and distribution on mechanical behavior of shape memory metallic glass composites by molecular dynamics method,” Journal of Alloys and Compounds. 2023. link Times cited: 0 J. Xi, F. Yang, X. Zhang, and H. Zhou, “Effect of geometry of crystalline dendrite on the uniaxial tension behavior of metallic glass matrix composites based on molecular dynamics simulations,” Materials Today Communications. 2023. link Times cited: 0 Y. Liu et al., “Investigations into the effect of cutting speed on nano-cutting of metallic glass by using molecular dynamics simulation analysis,” The International Journal of Advanced Manufacturing Technology. 2023. link Times cited: 1 P. Hopur, W. Chen, Y. Zhou, J. Zhou, and T. Wang, “The Correlation among the Atomic Structure, Electronic Valence Band and Properties of Zr-Cu-Al-Ag Bulk Metallic Glasses,” Metals. 2023. link Times cited: 0 Abstract: Investigating the relationship between the glass-forming abi… read more Abstract: Investigating the relationship between the glass-forming ability (GFA), mechanical properties, and structure of metallic glasses is crucial to understanding the nature of the metallic glass state. In this study, the correlation among the atomic structure, electronic valence band, and properties have been studied using Zr50Cu44.5−xAl5.5Agx (x = 0, 1.5, 3 at.%) bulk metallic glasses (BMGs). The results reveal that through the micro-addition of Ag, the GFA of Zr50Cu44.5Al5.5 BMG can be enhanced; meanwhile, the critical diameter of Zr50Cu44.5Al5.5 glass rods increases from approximately 2.5 mm to 5.0 mm with the addition of 3% Ag. Through the addition of Ag, the thermal stability of Zr50Cu44.5Al5.5 BMG is improved, and the proportion of icosahedral-like clusters increases. The plasticity of the Zr50Cu44.5−xAl5.5Agx (x = 0, 1.5, 3 at.%) BMGs decreased from 4.6% to 0.8% with the addition of Ag. The valence band spectrum of the Zr50Cu44.5−xAl5.5Agx (x = 0, 1.5, 3 at.%) BMGs indicates that with the addition of Ag, the p-d hybridization near the Fermi level is enhanced, and the binding energy will move to a lower value. read less X. Cui et al., “Investigations into effect of tool rake angle on nanocutting process for Zr-based amorphous alloy by molecular dynamics simulation,” The International Journal of Advanced Manufacturing Technology. 2023. link Times cited: 0 P. Garg and T. Rupert, “Local structural ordering determines the mechanical damage tolerance of amorphous grain boundary complexions,” Scripta Materialia. 2023. link Times cited: 0 X. Kong, W. Wang, M. Wang, and N. Hou, “Nanocutting mechanisms of Cu50Zr50 amorphous alloy: A molecular dynamics simulation,” Journal of Non-Crystalline Solids. 2023. link Times cited: 2 Y.-li Li, W. Wu, D. Şopu, and J. Eckert, “Effects of void shape and location on the fracture and plastic deformation of Cu (crystalline) /Cu64Zr36 (amorphous) composites,” Journal of Materials Research and Technology. 2023. link Times cited: 2 Y. Tang and H. Zhou, “High pressure heat treatment tuning cavitation behavior in FeP metallic glass,” Acta Mechanica Sinica. 2023. link Times cited: 0 W. H. Ryu et al., “Sustainable steady-state serrated flow induced by modulating deformation sequence in bulk metallic glass,” Journal of Alloys and Compounds. 2023. link Times cited: 2 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 A.-S. Tran, D.-Q. Doan, and V. Chu, “Molecular simulation study on mechanical properties and elastic recovery of nanoimprinted CuAgAu metallic glasses,” Journal of Non-Crystalline Solids. 2022. link Times cited: 4 Z. Xie, Y. Zhang, S. Huang, Z. Li, Q. Cheng, and J. Zhou, “Towards quantitative determination of atomic structures of amorphous materials in three dimensions,” National Science Open. 2022. link Times cited: 1 Abstract: : Amorphous materials such as glass, polymer and amorphous a… read more Abstract: : Amorphous materials such as glass, polymer and amorphous alloy have broad applications ranging from daily life to extreme conditions due to their unique properties in elasticity, strength and electrical resistivity. A better understanding of atomic structure of amorphous materials will provide invaluable information for their further engineering and applications. However, experimentally determining the three-dimensional (3D) atomic structure of amorphous materials has been a long-standing problem. Due to the disordered atomic arrangement, amorphous materials do not have any translational and rotational symmetry at long-range scale. Conventional characterization methods, such as the scattering and the microscopy imaging, can only provide the statistic structural information which is averaged over the macroscopic region. The knowledge of the 3D atomic structure of amorphous materials is limited. Recently atomic resolution electron tomography (AET) has proven an increasingly powerful tool for atomic scale structural characterization without any crystalline assumptions, which opens a door to determine the 3D structure of various amorphous materials. In this review, we summarize the state-of-art characterization methods for the exploration of atomic structures of amorphous materials in the past few decades, including X-ray/neutron diffraction, nano-beam and angstrom-beam electron diffraction, fluctuation electron microscopy, high-resolution scanning/ transmission electron microscopy, and atom probe tomography. From experimental data and theoretical descriptions, 3D structures of various amorphous materials have been built up. Particularly, we introduce the principles and recent progress of AET, and highlight the most recent groundbreaking feat accomplished by AET, i.e., the first experimental determination of all 3D atomic positions in a multi-component glass-forming alloy and the 3D atomic packing in amorphous solids. We also discuss the new opportunities and challenges for characterizing the chemical and structural defects in amorphous materials. read less L. Zhang et al., “Shear-band blunting governs superior mechanical properties of shape memory metallic glass composites,” Acta Materialia. 2022. link Times cited: 9 D. Şopu et al., “Rejuvenation engineering in metallic glasses by complementary stress and structure modulation,” NPG Asia Materials. 2022. link Times cited: 1 L.-li Zhou et al., “Topologically close-packed structure characteristics of the plastic deformation regions of amorphous Cu64.5Zr35.5,” Journal of Materials Research and Technology. 2022. link Times cited: 2 Y. Zhang, J. Xu, Y. Hu, S. Ding, and R. Xia, “Cold welding of ultrathin metallic glass nanowires with side-to-side contact using molecular dynamics simulations,” Materials Today Communications. 2022. link Times cited: 4 C. Liu, S. Yuan, J. Im, F. D. de Barros, S. Masri, and P. S. Branicio, “Mechanical Properties, Failure Mechanisms, and Scaling Laws of Bicontinuous Nanoporous Metallic Glasses,” Acta Materialia. 2022. link Times cited: 7 I. Patra, A. Abdulhadi, F. S. Fahim, B. S. Bashar, T. Alawsi, and M. Salmani, “The Effects of Temperature and Impact Velocity on the Shock Wave Response of Pore-Embedded Metallic Glasses,” Advances in Materials Science and Engineering. 2022. link Times cited: 2 Abstract: In this work, the shock wave response of a pore-embedded CuZ… read more Abstract: In this work, the shock wave response of a pore-embedded CuZr metallic glass (PEMG) under different impact velocities (0.5–1.5 km/s) and initial temperatures (300–600 K) was evaluated through the molecular dynamics (MD) simulation. The results indicated that the nucleation and growth of nanoscale shear events around the pore were the dominant mechanisms for plastic deformation under the shock wave. It was also found that the increase in the impact velocity led to the filling of pore, which was due to the structural softening and the local temperature increment in the vicinity of pore. Moreover, the spall event originated from the formation and coalescence of tension transformation zones, leading to the formation of nanovoids in the system. At higher velocities, the spallation was accompanied with the formation of more nanovoids with smaller sizes, inducing the brittle failure in the system. The MD outcomes also showed that the increase in initial temperature decreased the shock pressure and flow shear stress and led to the smoother spallation in the PEMG. read less W. Wu, Z.-S. Peng, D. Şopu, and J. Eckert, “Molecular dynamics study of fracture and plastic deformation of Cu/Cu64Zr36 crystalline/amorphous composites with a pre-existing void,” Journal of Non-Crystalline Solids. 2022. link Times cited: 4 G. Wei, J. Cui, W. Wang, X. Guo, J. Ren, and W. Wang, “Short-to-medium range structure and glass-forming ability in metallic glasses,” Physical Review Materials. 2022. link Times cited: 0 Y. Zhang, M. Cheng, L. Meng, and X. Yao, “Microstructural evolution of shear bands formation of metallic glasses under different loading conditions and strain rates,” Journal of Non-Crystalline Solids. 2022. link Times cited: 3 J. Zhang, X. Wang, M. Zhang, L. Deng, and P. Gong, “The shock forming process of Cu50Zr50 metallic glasses studied via molecular dynamics simulation,” Journal of Non-Crystalline Solids. 2022. link Times cited: 6 D. Bokov et al., “The effects of initial rejuvenation on the cold joining behavior of Cu60Zr40 metallic glass,” Applied Physics A. 2022. link Times cited: 2 G. Katakareddi and N. Yedla, “The effect of loading methods on the microstructural evolution and degree of strain localization in Cu50Zr50 metallic glass composite nanowires: A molecular dynamics simulation study.,” Journal of molecular graphics & modelling. 2022. link Times cited: 1 M. Müser, S. Sukhomlinov, and L. Pastewka, “Interatomic potentials: achievements and challenges,” Advances in Physics: X. 2022. link Times cited: 12 Abstract: ABSTRACT Interatomic potentials approximate the potential en… read more Abstract: ABSTRACT Interatomic potentials approximate the potential energy of atoms as a function of their coordinates. Their main application is the effective simulation of many-atom systems. Here, we review empirical interatomic potentials designed to reproduce elastic properties, defect energies, bond breaking, bond formation, and even redox reactions. We discuss popular two-body potentials, embedded-atom models for metals, bond-order potentials for covalently bonded systems, polarizable potentials including charge-transfer approaches for ionic systems and quantum-Drude oscillator models mimicking higher-order and many-body dispersion. Particular emphasis is laid on the question what constraints ensue from the functional form of a potential, e.g., in what way Cauchy relations for elastic tensor elements can be violated and what this entails for the ratio of defect and cohesive energies, or why the ratio of boiling to melting temperature tends to be large for potentials describing metals but small for short-ranged pair potentials. The review is meant to be pedagogical rather than encyclopedic. This is why we highlight potentials with functional forms sufficiently simple to remain amenable to analytical treatments. Our main objective is to provide a stimulus for how existing approaches can be advanced or meaningfully combined to extent the scope of simulations based on empirical potentials. Graphical abstract read less X. Yuan et al., “Maximizing the degree of rejuvenation in metallic glasses,” Scripta Materialia. 2022. link Times cited: 14 A. Abed et al., “The Characterization of Cold Welding Process in CuZr Metallic Glasses with Dissimilar Alloying Compositions,” Materials Today Communications. 2022. link Times cited: 4 X. Yuan, D. Şopu, K. Song, and J. Eckert, “Relaxation and Strain-Hardening Relationships in Highly Rejuvenated Metallic Glasses,” Materials. 2022. link Times cited: 6 Abstract: One way to rejuvenate metallic glasses is to increase their … read more Abstract: One way to rejuvenate metallic glasses is to increase their free volume. Here, by randomly removing atoms from the glass matrix, free volume is homogeneously generated in metallic glasses, and glassy states with different degrees of rejuvenation are designed and further mechanically tested. We find that the free volume in the rejuvenated glasses can be annihilated under tensile or compressive deformation that consequently leads to structural relaxation and strain-hardening. Additionally, the deformation mechanism of highly rejuvenated metallic glasses during the uniaxial loading–unloading tensile tests is investigated, in order to provide a systematic understanding of the relaxation and strain-hardening relationship. The observed strain-hardening in the highly rejuvenated metallic glasses corresponds to stress-driven structural and residual stress relaxation during cycling deformation. Nevertheless, the rejuvenated metallic glasses relax to a more stable state but could not recover their initial as-cast state. read less N. Amigo and F. Valencia, “Species Content Effect on the Rejuvenation Degree of CuZr Metallic Glasses Under Thermal-Pressure Treatments,” Metals and Materials International. 2022. link Times cited: 4 Y. Zhang, J. Li, Q. Zhang, S. Ding, W. Wu, and R. Xia, “Tetrachiral nanostructured metallic glasses with mechanically tunable performance,” Materials Chemistry and Physics. 2022. link Times cited: 3 T. Zhao, H. Song, M. An, and M. Xiao, “Effect of graphene on the mechanical properties of metallic glasses: Insight from molecular dynamics simulation,” Materials Chemistry and Physics. 2022. link Times cited: 3 S. Chupradit et al., “Role of Glass Composition on Mechanical Properties of Shape Memory Alloy-Metallic Glass Composites,” Advances in Materials Science and Engineering. 2021. link Times cited: 6 Abstract: In this work, the molecular dynamics (MD) simulation was app… read more Abstract: In this work, the molecular dynamics (MD) simulation was applied to design a laminated composite structure comprised of the shape memory alloy (SMA) and Cu-Zr metallic glasses (MGs). A wide range of MG compositions was considered to tune the mechanical features and improve the homogenous plastic deformation during the tension loading. The results indicated that the martensitic transformation in the SMA inhibited the sudden shear band propagation in the composite for all the samples. Moreover, it was revealed that the mechanism of plasticity was significantly affected by the change of MG composition. In the Cu-rich MGs, the formation and propagation of thick shear bands occurred at the end of the tension loading; however, the increase in Zr content induced the interaction of multiple shear bands with finer configurations in the system. Nevertheless, the excessive Zr addition in the MG composition facilitated the aggregation of nanopores at the interface of SMA and MGs, which may be due to the softening effect in the Zr-rich MGs. Finally, it is concluded that an optimized MG composition is required for the trade-off between the plasticity and the strength in the SMA-MG composites. read less Y. Zhang, J. Li, Y. Hu, S. Ding, F. Du, and R. Xia, “Characterization of the deformation behaviors under uniaxial stress for bicontinuous nanoporous amorphous alloys.,” Physical chemistry chemical physics : PCCP. 2021. link Times cited: 10 Abstract: In this paper, the deformation behaviors of Cu50Zr50 biconti… read more Abstract: In this paper, the deformation behaviors of Cu50Zr50 bicontinuous nanoporous amorphous alloys (BNAMs) under uniaxial tension/compression are explored by molecular dynamics simulations. Scaling laws between mechanical properties and relative density are investigated. The results demonstrate that the bending deformation of the ligament is the main elastic deformation mechanism under tension. Necking and subsequent fracture of ligaments are the primary failure mechanism under tension. Under tensile loading, shear bands emerge near the plastic hinges for the BNAMs with large porosities. The typical compressive behaviors of porous structure are observed in the BNAMs with large porosities. However, for small porosity, no distinguished plateau and densification are captured under compression. The tension-compression asymmetry of modulus increases with increasing porosity, whereas the BNAMs can be seen as tension-compression symmetry of yield strength. The modulus and yield strength are negatively correlated with temperature, but a positive relationship between the tensile ductility and temperature is shown. This work will help to provide a useful understanding of the mechanical behaviors of the BNAMs. read less T.-C. Chen et al., “Role of thermal history on atomic structure and ductility of ion-irradiated metallic glasses,” Modelling and Simulation in Materials Science and Engineering. 2021. link Times cited: 0 Abstract: Maximizing the structural rejuvenation and ductility is one … read more Abstract: Maximizing the structural rejuvenation and ductility is one of the most heated debates in the field of metallic glasses (MGs). In this work, molecular dynamics simulation was implemented to model the ion irradiation effects on the Cu60Zr40 MG with different thermal histories and varied structural heterogeneities. The initial results indicated that the performance of an annealing–quench treatment on the MG induces the atomic configurations with different heterogeneities and potential energy values. The subsequent ion irradiation process also demonstrated that an optimized atomic structure was occurred for achieving maximum rejuvenation and ductility in the CuZr glassy alloy. It was unveiled that the intermediate initial heterogeneity provides an efficient pathway for maximizing the atomic rearrangements under the ion irradiation. It was also suggested that the medium population of Cu-centered clusters in the initial state facilitated the atomic rearrangements during the ion irradiation process. The structural characteristics and atomic reconfigurations for attaining the optimum ductility is discussed in details. read less Y. Tang et al., “Tailoring microstructure of metallic glass for delocalized plasticity by pressure annealing: Forward and inverse studies,” Acta Materialia. 2021. link Times cited: 7 A. Agrawal and R. Mirzaeifar, “Computational investigation of deformation mechanisms at the atomistic scale of metallic glass-graphene composites (MGGCs),” Journal of Applied Physics. 2021. link Times cited: 1 Y. Zhang, J. Li, Y. Hu, S. Ding, F. Du, and R. Xia, “Mechanical properties and scaling laws of polycrystalline CuZr shape memory alloy,” Journal of Applied Physics. 2021. link Times cited: 5 Abstract: Thanks to their excellent properties such as superelasticity… read more Abstract: Thanks to their excellent properties such as superelasticity, high hardness, and shape memory effect, polycrystalline shape memory alloys (SMAs) have extensive applications in various engineering fields including automobile, functional materials, and aerospace. Using molecular dynamics simulations, the present paper aims to a systematic study of the fundamental tensile behavior in the nanoscale of polycrystalline B2-CuZr SMAs with mean grain sizes in the range of 6–25 nm. Effects of mean grain size, temperature, and tensile rate on mechanical properties are considered. Our results show that along with the increase in mean grain size came increases in Young's modulus, yield strength, flow stress, and ultimate tensile strength. The development of amorphous regions in the grain cores is the major deformation mode in polycrystalline CuZr SMAs with larger grain sizes, while the grain boundary sliding and grain rotation for smaller grain sizes. Besides, an increased temperature results in mechanical performance degradation and the temperature sensitivity of mechanical properties does not depend on the mean grain size. Our work would lay the groundwork for the optimization of the mechanical properties of polycrystalline SMAs as well as serving as a useful theoretical guideline for their practical engineering applications. read less A.-S. Tran, “Nanoindentation characteristics and recovery capacity of amorphous CuxTa100-x/Cu crystalline nanolaminates,” Journal of Non-crystalline Solids. 2021. link Times cited: 2 G. Katakareddi and N. Yedla, “Creep Behavior of Core (Metal)–Shell (Metallic Glass) Structure: a Molecular Dynamics Simulation Study,” Transactions of the Indian National Academy of Engineering. 2021. link Times cited: 1 K. E. Avila, S. Küchemann, and H. Urbassek, “Interaction between parallel shear bands in a metallic glass,” Journal of Non-crystalline Solids. 2021. link Times cited: 13 L. Shao, D. Chen, A. Zare, and D. Lucca, “Mechanism of nanocrystallization temperature shifting during ion irradiation of metallic glasses,” Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. 2021. link Times cited: 2 Y. Zhang, Y. Xian, J. Li, S. Ding, S. Liu, and R. Xia, “Atomistic investigation on the mechanical properties of 3D nanoporous metallic glasses under uniaxial tension and compression,” Materials today communications. 2021. link Times cited: 8 V. Vardanyan, K. E. Avila, S. Küchemann, and H. Urbassek, “Interaction of dislocations and shear bands in cutting of an amorphous-crystalline bilayer: An atomistic study,” Computational Materials Science. 2021. link Times cited: 10 A.-S. Tran, “Strengthening mechanism and plasticity deformation of crystalline/amorphous Cu/CuTa nanomultilayer,” Journal of Non-crystalline Solids. 2021. link Times cited: 6 X. Yuan, D. Şopu, and J. Eckert, “Origin of strain hardening in monolithic metallic glasses,” Physical Review B. 2021. link Times cited: 12 M. Paramonov, D. Minakov, V. Fokin, D. V. Knyazev, G. S. Demyanov, and P. Levashov, “Ab initio inspection of thermophysical experiments for zirconium near melting,” Journal of Applied Physics. 2021. link Times cited: 3 Abstract: We present quantum molecular dynamics calculations of thermo… read more Abstract: We present quantum molecular dynamics calculations of thermophysical properties of solid and liquid zirconium in the vicinity of melting. An overview of available experimental data is also presented. We focus on the analysis of thermal expansion, molar enthalpy, resistivity, and normal spectral emissivity of solid and liquid Zr. Possible reasons of discrepancies between the first-principles simulations and experiments are discussed. Our calculations reveal a significant volume change on melting in agreement with electrostatic levitation experiments. Meanwhile, we confirm a low value of enthalpy of fusion obtained in some pulse-heating experiments. Electrical resistivity of solid and liquid Zr is systematically underestimated in our simulations, however, the slope of resistivity temperature dependencies agrees with experiments. Our calculations predict almost constant normal spectral emissivity in liquid Zr. read less Y. L. Tang et al., “Extra plasticity governed by shear band deflection in gradient metallic glasses,” Nature Communications. 2021. link Times cited: 23 G. Mahmud, H. Zhang, and J. Douglas, “Localization model description of the interfacial dynamics of crystalline Cu and [Formula: see text] metallic glass nanoparticles.,” The European physical journal. E, Soft matter. 2021. link Times cited: 2 Y. Tang, H. F. Zhou, X. D. Wang, Q. Cao, D. X. Zhang, and J. Jiang, “Origin of different thermal cycling effects in Fe80P20 and Ni60Nb40 metallic glasses,” Materials Today Physics. 2021. link Times cited: 10 K. E. Avila, V. Vardanyan, S. Küchemann, and H. Urbassek, “Response of an amorphous/crystalline interface to nanoindentation: an atomistic study,” Applied Surface Science. 2021. link Times cited: 13 A.-S. Tran and T. Fang, “The influence of intrinsic size in amorphous CuxTa100-x/Cu crystalline nanolaminates using molecular dynamics simulation,” Physica E-low-dimensional Systems & Nanostructures. 2021. link Times cited: 7 C. Liu, S. Yuan, and P. S. Branicio, “Bicontinuous Nanoporous Design Induced Homogenization of Strain Localization in Metallic Glasses,” EngRN: Dynamical System (Topic). 2021. link Times cited: 15 Abstract: Bicontinuous nanoporous metallic glasses (MG) synergize the … read more Abstract: Bicontinuous nanoporous metallic glasses (MG) synergize the outstanding properties of MGs and open-cell nanoporous materials. The low-density and high-specific-surface-area of bicontinuous nanoporous structures have the potential to enhance the applicability of MGs in catalysis, sensors, and lightweight structural designs. Here, we report molecular dynamics simulations of tensile loading deformation and failure of bicontinuous nanoporous Cu64Zr36 MG with 55% porosity and 4.4 nm ligament size. Results indicate an anomalous mechanical behavior featuring delocalized plastic deformation preceding ductile failure. The deformation follows two mechanisms: i) Necking of ligaments aligned with the loading direction and ii) progressive alignment of randomly oriented ligaments. Failure occurs at 0.16 strain, following massive rupture of ligaments. This work indicates that a bicontinuous nanoporous design is able to effectively delocalize strain localization in a MG due to a combination of size effect on the ductility of MGs resulting in nano ligaments necking and progressive asynchronous alignment of ligaments. read less W. Li, H. Y. Song, J. Dai, J. Wang, M. An, and Y. Li, “Effect of shape memory alloys on the mechanical properties of metallic glasses: A molecular dynamics study,” Computational Materials Science. 2021. link Times cited: 9 S. Li, P. Huang, and F. Wang, “Achieving pronounced β-relaxations and improved plasticity in CuZr metallic glass,” Journal of Alloys and Compounds. 2021. link Times cited: 2 K. E. Avila, V. Vardanyan, I. A. Alhafez, M. Zimmermann, B. Kirsch, and H. Urbassek, “Applicability of cutting theory to nanocutting of metallic glasses: Atomistic simulation,” Journal of Non-crystalline Solids. 2020. link Times cited: 16 J. Li et al., “A concurrent high strength and ductility of 3D gyroidal nanoporous metallic glasses,” Journal of Non-crystalline Solids. 2020. link Times cited: 7 K. N. Lad and K. Soni, “Effect of Al addition on structure and dynamics of Zr-Cu-Al glass-forming alloy,” Materials Today: Proceedings. 2020. link Times cited: 1 J. Ma, H. Y. Song, M. An, W. Li, and R. Han, “A strategy for improving mechanical properties of metallic glass by tailoring interface structure,” Journal of Non-crystalline Solids. 2020. link Times cited: 6 A.-S. Tran and T. Fang, “Effects of grain size and indentation sensitivity on deformation mechanism of nanocrystalline tantalum,” International Journal of Refractory Metals & Hard Materials. 2020. link Times cited: 6 A.-S. Tran and T. Fang, “Size effect and interfacial strength in nanolaminated Cu/CuxTa100-x composites using molecular dynamics,” Computational Materials Science. 2020. link Times cited: 12 T. Dutta, A. Chauniyal, I. Singh, and R. Narasimhan, “Numerical investigation of tensile response of notched bulk metallic glass composite specimens,” Modelling and Simulation in Materials Science and Engineering. 2020. link Times cited: 3 Abstract: In this work, plane strain finite element and atomistic simu… read more Abstract: In this work, plane strain finite element and atomistic simulations of tensile response of double edge notched bulk metallic glass composite (BMGC) samples are conducted. A special constitutive model is used to represent the response of the bulk metallic glass matrix along with J 2 flow theory of plasticity to characterize the crystalline dendrites in the former, while a CuZr based glass matrix containing single crystal Cu dendrites is modeled in the latter. It is found that the ratio of notch root radius to the distance between the notch tip and the nearest dendrite, R/l 1, is an important parameter that governs the plastic deformation behavior and possible failure mechanisms. Both finite element and atomistic analyses show that as R/l 1 increases from a small to moderate value, a transition occurs in plastic flow through multiple shear banding with deflection by dendrites to ligament necking. On further increase in the above notch acuity parameter, the deformation behavior again changes to multiple shear banding without much hindrance from dendrites. Specimens with moderately blunt notches (as characterized by the value of R/l 1) having high hardening elongated dendrites exhibit pronounced plastic deformation along the ligament resulting in necking. The influence of BMGC microstructure and hardening of dendrites is also investigated from the finite element analyses. read less Z. Xie, W. Jian, X. Tang, X. Zhang, and X. Yao, “Strengthening and toughening mechanisms of metallic glass nanocomposites via graphene nanoplatelets,” Journal of Non-crystalline Solids. 2020. link Times cited: 4 H. Y. Song, B. Duan, Y. Wang, M. An, and Y. L. Li, “Enhanced plasticity by introducing amorphous phase in nanopolycrystal Cu: A molecular dynamics study,” Materials Chemistry and Physics. 2020. link Times cited: 4 Q. Zhang, Q. Li, and M. Li, “From deformation localization to melting and chemical segregation in metallic glass nanoparticles under high strain rate,” Journal of Applied Physics. 2020. link Times cited: 0 Abstract: Nanoparticles possess many distinguished properties due to t… read more Abstract: Nanoparticles possess many distinguished properties due to their small size and unique internal and surface structures. For metallic glass nanoparticles, the small size combined with disordered atomic structure results in many unexpected results, some of which are superior to crystalline particles. This field, however, remains largely unexplored. Here, we report the mechanical and thermomechanical responses caused by the increasing strain rate in metallic glass nanoparticles under compression. The mechanical properties of nanoparticles resemble those of the bulk when the strain rate is below 1010 s−1; above this threshold, the nanoparticle exhibits localized deformation and then melting and even chemical segregation at the contact surface area. We reveal that these unique behaviors are the direct results of the lack of effective energy dissipation mechanisms in the disordered materials that are different from crystalline nanoparticles. read less A.-S. Tran, “Phase transformation and interface fracture of Cu/Ta multilayers: A molecular dynamics study,” Engineering Fracture Mechanics. 2020. link Times cited: 16 S. Yuan, X. Song, and P. S. Branicio, “Tuning the Mechanical Properties of Shape Memory Metallic Glass Composites with Brick and Mortar Designs,” Scripta Materialia. 2020. link Times cited: 18 B. Fan, K. Han, H. P. Zhang, and M. Li, “Low-frequency vibrational properties and structure correlation in metallic glass,” Journal of Non-crystalline Solids. 2020. link Times cited: 0 J. Houška, P. Machanova, M. Zítek, and P. Zeman, “Molecular dynamics and experimental study of the growth, structure and properties of Zr–Cu films,” Journal of Alloys and Compounds. 2020. link Times cited: 11 D.-Q. Doan, T. Fang, and T.-H. Chen, “Nanotribological characteristics and strain hardening of amorphous Cu64Zr36/ crystalline Cu nanolaminates,” Tribology International. 2020. link Times cited: 36 M. Wang, H. Liu, J. Li, Q. Jiang, W. Yang, and C. Tang, “Thermal-pressure treatment for tuning the atomic structure of metallic glass Cu-Zr,” Journal of Non-crystalline Solids. 2020. link Times cited: 12 Z. Xie, W. Jian, Z. Wang, X. Zhang, and X. Yao, “Layer thickness effects on the strengthening and toughening mechanisms in metallic glass-graphene nanolaminates,” Computational Materials Science. 2020. link Times cited: 17 R. Jana, J. von Lautz, S. M. Khosrownejad, W. Andrews, M. Moseler, and L. Pastewka, “Constitutive relations for plasticity of amorphous carbon,” Journal of Physics: Materials. 2020. link Times cited: 5 Abstract: We deform representative volume elements of amorphous carbon… read more Abstract: We deform representative volume elements of amorphous carbon obtained from melt-quenches in molecular dynamics calculations using bond-order and machine learning interatomic potentials. A Drucker-Prager law with a zero-pressure flow stress of 41.2 GPa and an internal friction coefficient of 0.39 describes the deviatoric stress during flow as a function of pressure. We identify the mean coordination number as the order parameter describing this flow surface. However, a description of the dynamical relaxation of the quenched samples towards steady-state flow requires an additional order parameter. We suggest an intrinsic strain of the samples and present equations for its evolution. Our results provide insights into rehybridization and pressure dependence of friction between coated surfaces as well as routes towards the description of amorphous carbon in macroscale models of deformation. read less D. Şopu, S. Scudino, X. L. Bian, C. Gammer, and J. Eckert, “Atomic-scale origin of shear band multiplication in heterogeneous metallic glasses,” Scripta Materialia. 2020. link Times cited: 74 D.-Q. Doan, T. Fang, A.-S. Tran, and T.-H. Chen, “High deformation capacity and dynamic shear band propagation of imprinted amorphous Cu50Zr50/crystalline Cu multilayered nanofilms,” Journal of Physics and Chemistry of Solids. 2020. link Times cited: 23 J. Mo, H. Liu, Z. Chen, Y. Z. He, W. Yang, and B. Shen, “Estimation of the glass-forming ability of metallic glasses with monolayer two-dimensional model,” Computational Materials Science. 2020. link Times cited: 0 D.-Q. Doan, T. Fang, A.-S. Tran, and T.-H. Chen, “Residual stress and elastic recovery of imprinted Cu-Zr metallic glass films using molecular dynamic simulation,” Computational Materials Science. 2019. link Times cited: 46 L. Chen et al., “Correlation of viscosity with atomic packing in Cu50Zr50 melt,” Journal of Molecular Liquids. 2019. link Times cited: 9 A.-S. Tran and T. Fang, “Void growth and coalescence in Cu-Ta metallic glasses using molecular dynamics,” Computational Materials Science. 2019. link Times cited: 21 X. Zhou, L. Wang, and C. Chen, “Improving ductility of nanoporous metallic glasses,” Computational Materials Science. 2019. link Times cited: 15 S. Li, P. Huang, and F. Wang, “Rejuvenation saturation upon cyclic elastic loading in metallic glass,” Computational Materials Science. 2019. link Times cited: 21 K. Kosiba, D. Şopu, S. Scudino, L. Zhang, J. Bednarčík, and S. Pauly, “Modulating heterogeneity and plasticity in bulk metallic glasses: Role of interfaces on shear banding,” International Journal of Plasticity. 2019. link Times cited: 76 D. Zhao, S. Wang, B. Zhu, L. Li, and H. Zhao, “Anisotropic deformation behaviors of amorphous-crystalline nanolaminates investigated via molecular dynamics simulations,” Journal of Alloys and Compounds. 2019. link Times cited: 10 B. Cheng and J. Trelewicz, “Controlling interface structure in nanoglasses produced through hydrostatic compression of amorphous nanoparticles,” Physical Review Materials. 2019. link Times cited: 12 Abstract: Controlling glass-glass interfaces in metallic nanoglasses i… read more Abstract: Controlling glass-glass interfaces in metallic nanoglasses is essential for tuning their mechanical properties and in particular, the ability to inhibit severe strain localization through distributed shear band formation. In this paper, molecular dynamics are employed to quantify the structural characteristics of interfaces in a scalable nanoglass model produced through hydrostatic compression of amorphous nanoparticles. Using a framework for distinguishing interfaces from amorphous grains based on the correlation between dilatation and atomic volume distributions, we show that the interfaces in our nanoglass model exhibit a volume fraction of 0.36, a width of approximately 2 nm, excess free volume of 1--2%, and full icosahedral (FI) fraction roughly 30% that of a bulk metallic glass counterpart. While these characteristics are quantitatively unique relative to other nanoglass models (e.g., planar interfaces and Poisson-Voronoi constructions), they are consistent with experimental results reported for nanoglasses consolidated from glassy nanoparticles produced through inert gas condensation. Increasing the consolidation temperature enhanced the FI fraction with a strong bias to the interfaces, thus demonstrating a route for tuning interfacial properties in nanoglasses. read less S. Ketov et al., “High-resolution transmission electron microscopy investigation of diffusion in metallic glass multilayer films,” Materials Today Advances. 2019. link Times cited: 13 H. Y. Song, M. Wang, M. An, and Y. L. Li, “Enhancing the plasticity of noncrystalline Cu Zr multilayer: Insights from molecular dynamics simulations,” Journal of Non-Crystalline Solids. 2019. link Times cited: 5 H. Song, J. J. Xu, Q. Deng, and Y. Li, “Effect of interface structure on deformation behavior of crystalline Cu/amorphous CuZr sandwich structures,” Physics Letters A. 2019. link Times cited: 8 M. Wang et al., “Thermal-pressure effects on energy state of metallic glass Cu50Zr50,” Computational Materials Science. 2018. link Times cited: 17 W. Jian, L. Wang, X. Yao, and S. Luo, “Tensile and nanoindentation deformation of amorphous/crystalline nanolaminates: Effects of layer thickness and interface type,” Computational Materials Science. 2018. link Times cited: 28 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 more Abstract: 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 K. Zhou, T. Zhang, B. Liu, and Y. Yao, “Atomistic simulations of the effect of Zr addition on the microstructure and plastic deformation of nanocrystalline copper,” Physica B: Condensed Matter. 2018. link Times cited: 2 D. Şopu, K. Albe, and J. Eckert, “Metallic glass nanolaminates with shape memory alloys,” Acta Materialia. 2018. link Times cited: 38 J. Feng, P. Chen, and M. Li, “Existence of fractal packing in metallic glasses: Molecular dynamics simulations ofCu46Zr54,” Physical Review B. 2018. link Times cited: 7 Y. Zhang et al., “Atomic-scale structural evolution in selective laser melting of Cu50Zr50 metallic glass,” Computational Materials Science. 2018. link Times cited: 30 B. Cheng and J. Trelewicz, “Design of crystalline-amorphous nanolaminates using deformation mechanism maps,” Acta Materialia. 2018. link Times cited: 34 H. Y. Song, S. Li, M. An, Q. Deng, and Y. L. Li, “Effect of crystal phase on shear bands initiation and propagation behavior in metallic glass matrix composites,” Computational Materials Science. 2018. link Times cited: 9 H. Y. Song, M. Wang, Q. Deng, and Y. L. Li, “Deformation mode transitions in Cu 50 Zr 50 amorphous/Cu crystalline nanomultilayer: A molecular dynamics study,” Journal of Non-Crystalline Solids. 2018. link Times cited: 21 C. Wu and C. Hou, “Molecular dynamics analysis of plastic deformation and mechanics of imprinted metallic glass films,” Computational Materials Science. 2018. link Times cited: 23 M. Sepulveda-Macias, N. Amigo, and G. Gutiérrez, “Tensile behavior of Cu 50 Zr 50 metallic glass nanowire with a B2 crystalline precipitate,” Physica B-condensed Matter. 2018. link Times cited: 21 T. Dutta, A. Chauniyal, I. Singh, R. Narasimhan, T. P. G. Thamburaja, and U. Ramamurty, “Plastic deformation and failure mechanisms in nano-scale notched metallic glass specimens under tensile loading,” Journal of The Mechanics and Physics of Solids. 2018. link Times cited: 33 B. Wang, G. Kang, Q. Kan, W. Wu, K. Zhou, and C. Yu, “Atomistic study on the super-elasticity of single crystal bulk NiTi shape memory alloy under adiabatic condition,” Computational Materials Science. 2018. link Times cited: 24 J. Yu, M. Wang, and S. Lin, “Slower icosahedral cluster rejuvenation drives the brittle-to-ductile transition in nanoscale metallic glasses,” Computational Materials Science. 2017. link Times cited: 17 H. Y. Song, S. Li, and Q. Deng, “Coupling effects of thickness and aspect ratio on deformation behavior of Cu50Zr50 metallic glass,” Computational Materials Science. 2017. link Times cited: 26 M. Kozłowski, D. Scopece, J. Janczak-Rusch, L. Jeurgens, R. Abdank-Kozubski, and D. Passerone, “Validation of an Embedded-Atom Copper Classical Potential via Bulk and Nanostructure Simulations,” Diffusion Foundations. 2017. link Times cited: 0 Abstract: The validation of classical potentials for describing multic… read more Abstract: The validation of classical potentials for describing multicomponent materials in complex geometries and their high temperature structural modifications (disordering and melting) requires to verify both a faithful description of the individual phases and a convincing scheme for the mixed interactions, like it is the case of the embedded atom scheme. The present paper addresses the former task for an embedded atom potential for copper, namely the widely adopted parametrization by Zhou, through application to bulk, surface and nanocluster systems. It is found that the melting point is underestimated by 200 degrees with respect to experiment, but structural and temperature-dependent properties are otherwise faithfully reproduced. read less H. Y. Song, S. Li, Y. G. Zhang, Q. Deng, T. H. Xu, and Y. L. Li, “Atomic simulations of plastic deformation behavior of Cu 50 Zr 50 metallic glass,” Journal of Non-crystalline Solids. 2017. link Times cited: 29 H. Y. Song, J. Xu, Y. G. Zhang, S. Li, D. Wang, and Y. L. Li, “Molecular dynamics study of deformation behavior of crystalline Cu/amorphous Cu50Zr50 nanolaminates,” Materials & Design. 2017. link Times cited: 58 C. Zhong, Q. Cao, X. Wang, D. Zhang, H. Fecht, and J. Jiang, “Relationship of deformation mode with strain-dependent shear transformation zone size in Cu-Zr metallic glasses using molecular dynamics simulations,” Journal of Non-crystalline Solids. 2017. link Times cited: 8 B. Ding and X. Li, “An Eccentric Ellipse Failure Criterion for Amorphous Materials,” Journal of Applied Mechanics. 2017. link Times cited: 7 T. W. Wu et al., “The compressive behaviour after crystallisation in Zr85Cu15 metallic glasses studied by molecular dynamics simulations,” Journal of Non-crystalline Solids. 2017. link Times cited: 5 L. Lang et al., “Molecular dynamics simulations of the structure evolutions of Cu-Zr metallic glasses under irradiation,” Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms. 2017. link Times cited: 9 Y.-chen Cui, Y. Shibutani, S. Li, P. Huang, and F. Wang, “Plastic deformation behaviors of amorphous-Cu50Zr50/crystalline-Cu nanolaminated structures by molecular dynamics simulations,” Journal of Alloys and Compounds. 2017. link Times cited: 42 Q. Zhang, Q. Li, and M. Li, “Key factors affecting mechanical behavior of metallic glass nanowires,” Scientific Reports. 2017. link Times cited: 19 S. Pan, Z. W. Wu, W.-chao Wang, M. Li, and L. Xu, “Structural origin of fractional Stokes-Einstein relation in glass-forming liquids,” Scientific Reports. 2017. link Times cited: 27 C. Zhong et al., “Deformation behavior of metallic glasses with shear band like atomic structure: a molecular dynamics study,” Scientific Reports. 2016. link Times cited: 40 C. Zhong et al., “Size distribution of shear transformation zones and. their evolution towards the formation of shear bands in metallic glasses,” Journal of Non-crystalline Solids. 2016. link Times cited: 22 W. Zhao, C. Jialin, S. Feng, G. Li, and R. Liu, “Intrinsic correlation between elastic modulus and atomic bond stiffness in metallic glasses,” Materials Letters. 2016. link Times cited: 11 D. Şopu, A. Foroughi, M. Stoica, and J. Eckert, “Brittle-to-Ductile Transition in Metallic Glass Nanowires.,” Nano letters. 2016. link Times cited: 84 Abstract: When reducing the size of metallic glass samples down to the… read more Abstract: When reducing the size of metallic glass samples down to the nanoscale regime, experimental studies on the plasticity under uniaxial tension show a wide range of failure modes ranging from brittle to ductile ones. Simulations on the deformation behavior of nanoscaled metallic glasses report an unusual extended strain softening and are not able to reproduce the brittle-like fracture deformation as found in experiments. Using large-scale molecular dynamics simulations we provide an atomistic understanding of the deformation mechanisms of metallic glass nanowires and differentiate the extrinsic size effects and aspect ratio contribution to plasticity. A model for predicting the critical nanowire aspect ratio for the ductile-to-brittle transition is developed. Furthermore, the structure of brittle nanowires can be tuned to a softer phase characterized by a defective short-range order and an excess free volume upon systematic structural rejuvenation, leading to enhanced tensile ductility. The presented results shed light on the fundamental deformation mechanisms of nanoscaled metallic glasses and demarcate ductile and catastrophic failure. read less 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 more Abstract: 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 S. Feng et al., “Structural feature of Cu64Zr36 metallic glass on nanoscale: Densely-packed clusters with loosely-packed surroundings,” Scripta Materialia. 2016. link Times cited: 36 C. Zhong et al., “On the critical thickness for non-localized to localized plastic flow transition in metallic glasses: A molecular dynamics study,” Scripta Materialia. 2016. link Times cited: 47 S. Chattopadhyay et al., “Local structure, composition, and crystallization mechanism of a model two-phase ‘composite nanoglass’.,” The Journal of chemical physics. 2016. link Times cited: 3 Abstract: We report a detailed study of the local composition and stru… read more Abstract: We report a detailed study of the local composition and structure of a model, bi-phasic nanoglass with nominal stoichiometry Cu55Nb45. Three dimensional atom probe data suggest a nanoscale-phase-separated glassy structure having well defined Cu-rich and Nb-rich regions with a characteristic length scale of ≈ 3 nm. However, extended x-ray absorption fine structure analysis indicates subtle differences in the local environments of Cu and Nb. While the Cu atoms displayed a strong tendency to cluster and negligible structural order beyond the first coordination shell, the Nb atoms had a larger fraction of unlike neighbors (higher chemical order) and a distinctly better-ordered structural environment (higher topological order). This provides the first experimental indication that metallic glass formation may occur due to frustration arising from the competition between chemical ordering and clustering. These observations are complemented by classical as well as ab initio molecular dynamics simulations. Our study indicates that these nanoscale phase-separated glasses are quite distinct from the single phase nanoglasses (studied by Gleiter and others) in the following three respects: (i) they contain at least two structurally and compositionally distinct, nanodispersed, glassy phases, (ii) these phases are separated by comparatively sharp inter-phase boundaries, and (iii) thermally induced crystallization occurs via a complex, multi-step mechanism. Such materials, therefore, appear to constitute a new class of disordered systems that may be called a composite nanoglass. read less X. Zhou, H. Zhou, X. Li, and C. Chen, “Size effects on tensile and compressive strengths in metallic glass nanowires,” Journal of The Mechanics and Physics of Solids. 2015. link Times cited: 60 D. Wen, P. Peng, Y.-qi Jiang, Z.-an Tian, W. Li, and R.-su Liu, “Correlation of the heredity of icosahedral clusters with the glass forming ability of rapidly solidified CuxZr100 − x alloys,” Journal of Non-crystalline Solids. 2015. link Times cited: 24 B. Sun and W. Wang, “The fracture of bulk metallic glasses,” Progress in Materials Science. 2015. link Times cited: 406 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 more Abstract: 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 L. Gao, S. Feng, L. Qi, F. Zhao, and R. P. Liu, “Effects of nanocrystals on evolution behavior of shear transformation zones in Zr85Cu15 metallic glasses,” Journal of Non-crystalline Solids. 2015. link Times cited: 4 J. Luo and Y. Shi, “The local stress state of a running shear band in amorphous solids,” Journal of Materials Research. 2015. link Times cited: 7 Abstract: In molecular dynamics simulations, the local stress state in… read more Abstract: In molecular dynamics simulations, the local stress state in the shear band is examined in six different model metallic glasses and one amorphous Si system (also has been perceived as a metallic glass analog) under different loading conditions. For all but the FeP and the amorphous Si systems, the running shear band (RSB) exhibits a liquid-like hydrostatic plus shear stress state. Our results suggest that the liquid feature of a RSB is not due to temperature rise or plastic confinement but due to the disorder driven by flow, which can be offset by strong directionality in bonding, phase segregation, or aging. The knowledge of the liquid-like stress state can be conveniently utilized in experiments to infer the local stress state of the RSB from the global tensile stress for metallic glasses. read less D. Şopu, M. Stoica, and J. Eckert, “Deformation behavior of metallic glass composites reinforced with shape memory nanowires studied via molecular dynamics simulations,” Applied Physics Letters. 2015. link Times cited: 56 Abstract: Molecular dynamics simulations indicate that the deformation… read more Abstract: Molecular dynamics simulations indicate that the deformation behavior and mechanism of Cu64Zr36 composite structures reinforced with B2 CuZr nanowires are strongly influenced by the martensitic phase transformation and distribution of these crystalline precipitates. When nanowires are distributed in the glassy matrix along the deformation direction, a two-steps stress-induced martensitic phase transformation is observed. Since the martensitic transformation is driven by the elastic energy release, the strain localization behavior in the glassy matrix is strongly affected. Therefore, the composite materials reinforced with a crystalline phase, which shows stress-induced martensitic transformation, represent a route for controlling the properties of glassy materials. read less Y. Mo et al., “Non-linear effects of initial melt temperatures on microstructures and mechanical properties during quenching process of liquid Cu46Zr54 alloy,” Physica B-condensed Matter. 2015. link Times cited: 5 C. Zhong, H. Zhang, Q. Cao, W. Xiaodong, D. X. Zhang, and J. Jiang, “The size-dependent non-localized deformation in a metallic alloy,” Scripta Materialia. 2015. link Times cited: 51 X. Zhou and C. Chen, “Molecular dynamic simulations of the mechanical properties of crystalline/crystalline and crystalline/amorphous nanolayered pillars,” Computational Materials Science. 2015. link Times cited: 18 Y. Mo et al., “Formation and evolution of nano-clusters in a large-scale system of Cu–Zr alloy during rapid solidification process,” Computational Materials Science. 2015. link Times cited: 14 Y. Hu, D. Wen, Y.-qi Jiang, Y. Deng, and P. Peng, “Effect of cooling rates on clustering towards icosahedra in rapidly solidified Cu56Zr44 alloy,” Transactions of Nonferrous Metals Society of China. 2015. link Times cited: 6 Y. Hiraoka, T. Nakamura, A. Hirata, E. G. Escolar, K. Matsue, and Y. Nishiura, “Hierarchical structures of amorphous solids characterized by persistent homology,” Proceedings of the National Academy of Sciences. 2015. link Times cited: 253 Abstract: Significance Persistent homology is an emerging mathematical… read more Abstract: Significance Persistent homology is an emerging mathematical concept for characterizing shapes of data. In particular, it provides a tool called the persistence diagram that extracts multiscale topological features such as rings and cavities embedded in atomic configurations. This article presents a unified method using persistence diagrams for studying the geometry of atomic configurations in amorphous solids. The method highlights hierarchical structures that conventional techniques could not have treated appropriately. This article proposes a topological method that extracts hierarchical structures of various amorphous solids. The method is based on the persistence diagram (PD), a mathematical tool for capturing shapes of multiscale data. The input to the PDs is given by an atomic configuration and the output is expressed as 2D histograms. Then, specific distributions such as curves and islands in the PDs identify meaningful shape characteristics of the atomic configuration. Although the method can be applied to a wide variety of disordered systems, it is applied here to silica glass, the Lennard-Jones system, and Cu-Zr metallic glass as standard examples of continuous random network and random packing structures. In silica glass, the method classified the atomic rings as short-range and medium-range orders and unveiled hierarchical ring structures among them. These detailed geometric characterizations clarified a real space origin of the first sharp diffraction peak and also indicated that PDs contain information on elastic response. Even in the Lennard-Jones system and Cu-Zr metallic glass, the hierarchical structures in the atomic configurations were derived in a similar way using PDs, although the glass structures and properties substantially differ from silica glass. These results suggest that the PDs provide a unified method that extracts greater depth of geometric information in amorphous solids than conventional methods. read less K. N. Lad, “Correlation between atomic-level structure, packing efficiency and glass-forming ability in Cu–Zr metallic glasses,” Journal of Non-crystalline Solids. 2014. link Times cited: 16 A. Nakamura, Y. Kamimura, K. Edagawa, and S. Takeuchi, “Elastic and plastic characteristics of a model Cu–Zr amorphous alloy,” Materials Science and Engineering A-structural Materials Properties Microstructure and Processing. 2014. link Times cited: 4 M. Li, “Correlation Between Local Atomic Symmetry and Mechanical Properties in Metallic Glasses,” Journal of Materials Science & Technology. 2014. link Times cited: 32 C. Wu, N. Karayiannis, M. Laso, D. Qu, Q. Luo, and J. Shen, “A metric to gauge local distortion in metallic glasses and supercooled liquids,” Acta Materialia. 2014. link Times cited: 9 F. Li, X. Liu, and Z. Lu, “Atomic structural evolution during glass formation of a Cu–Zr binary metallic glass,” Computational Materials Science. 2014. link Times cited: 56 D. Wen, P. Peng, Y.-qi Jiang, Z.-an Tian, R.-su Liu, and K. Dong, “The effect of cooling rates on hereditary characteristics of icosahedral clusters in rapid solidification of liquid Cu56Zr44 alloys,” Journal of Non-crystalline Solids. 2014. link Times cited: 12 H. Gleiter, T. Schimmel, and H. Hahn, “Nanostructured solids – From nano-glasses to quantum transistors,” Nano Today. 2014. link Times cited: 108 K. Albe, Y. Ritter, and D. Şopu, “Enhancing the plasticity of metallic glasses: Shear band formation, nanocomposites and nanoglasses investigated by molecular dynamics simulations,” Mechanics of Materials. 2013. link Times cited: 163 D. Wen, P. Peng, Y.-qi Jiang, and R.-su Liu, “On the heredity and evolution of icosahedral clusters during the rapid solidification of liquid Cu50Zr50 alloys,” Journal of Non-crystalline Solids. 2013. link Times cited: 25 R. Soklaski, Z. Nussinov, Z. E. Markow, K. Kelton, and L. Yang, “Connectivity of icosahedral network and a dramatically growing static length scale in Cu-Zr binary metallic glasses,” Physical Review B. 2013. link Times cited: 126 Abstract: We report on and characterize, via molecular dynamics studie… read more Abstract: We report on and characterize, via molecular dynamics studies, the evolution of the structure of Cu${}_{50}$Zr${}_{50}$ and Cu${}_{64}$Zr${}_{36}$ metallic glasses (MGs) as temperature is varied. Interestingly, a percolating icosahedral network appears in the Cu${}_{64}$Zr${}_{36}$ system as it is supercooled. This leads us to introduce a static length scale, which grows dramatically as this three-dimensional system approaches the glass transition. Amidst interpenetrating connections, noninterpenetrating connections between icosahedra are shown to become prevalent upon supercooling and to greatly enhance the connectivity of the MG's icosahedral network. Additionally, we characterize the chemical compositions of the icosahedral networks and their components. These findings demonstrate the importance of noninterpenetrating connections for facilitating extensive structural networks in Cu-Zr MGs, which in turn drive dynamical slowing in these materials. read less S. Pan, J. Qin, W. Wang, and T. Gu, “A new method to characterize medium range order in metallic glasses,” Journal of Non-crystalline Solids. 2012. link Times cited: 7 D. Miracle, K. Laws, O. Senkov, and G. Wilks, “Partial Coordination Numbers in Binary Metallic Glasses,” Metallurgical and Materials Transactions A. 2012. link Times cited: 16 J. Schäfer, Y. Ashkenazy, K. Albe, and R. Averback, “Effect of solute segregation on thermal creep in dilute nanocyrstalline Cu alloys,” Materials Science and Engineering A-structural Materials Properties Microstructure and Processing. 2012. link Times cited: 17 A. Lagogianni, D. Papageorgiou, and G. Evangelakis, “Surface properties of the Cu50Zr50 metallic glass decorated with icosahedral CuxZr100−x (0 < x < 100) clusters by molecular dynamics simulations,” Computational Materials Science. 2012. link Times cited: 9 Y. Ritter and K. Albe, “Thermal annealing of shear bands in deformed metallic glasses: Recovery mechanisms in Cu64Zr36 studied by molecular dynamics simulations,” Acta Materialia. 2011. link Times cited: 24 Y. Ritter, D. Şopu, H. Gleiter, and K. Albe, “Structure, stability and mechanical properties of internal interfaces in Cu64Zr36 nanoglasses studied by MD simulations,” Acta Materialia. 2011. link Times cited: 98 J. Harvey, A. Gheribi, and P. Chartrand, “Accurate determination of the Gibbs energy of Cu-Zr melts using the thermodynamic integration method in Monte Carlo simulations.,” The Journal of chemical physics. 2011. link Times cited: 19 Abstract: The design of multicomponent alloys used in different applic… read more Abstract: The design of multicomponent alloys used in different applications based on specific thermo-physical properties determined experimentally or predicted from theoretical calculations is of major importance in many engineering applications. A procedure based on Monte Carlo simulations (MCS) and the thermodynamic integration (TI) method to improve the quality of the predicted thermodynamic properties calculated from classical thermodynamic calculations is presented in this study. The Gibbs energy function of the liquid phase of the Cu-Zr system at 1800 K has been determined based on this approach. The internal structure of Cu-Zr melts and amorphous alloys at different temperatures, as well as other physical properties were also obtained from MCS in which the phase trajectory was modeled by the modified embedded atom model formalism. A rigorous comparison between available experimental data and simulated thermo-physical properties obtained from our MCS is presented in this work. The modified quasichemical model in the pair approximation was parameterized using the internal structure data obtained from our MCS and the precise Gibbs energy function calculated at 1800 K from the TI method. The predicted activity of copper in Cu-Zr melts at 1499 K obtained from our thermodynamic optimization was corroborated by experimental data found in the literature. The validity of the amplitude of the entropy of mixing obtained from the in silico procedure presented in this work was analyzed based on the thermodynamic description of hard sphere mixtures. read less K. Park, E. Fleury, H. Seok, and Y.-C. Kim, “Deformation behaviors under tension and compression: Atomic simulation of Cu65Zr35 metallic glass,” Intermetallics. 2011. link Times cited: 17 K. Park, H. Park, and E. Fleury, “Strain localization in annealed Cu50Zr50 metallic glass,” Materials Science and Engineering A-structural Materials Properties Microstructure and Processing. 2011. link Times cited: 7 D. Şopu, Y. Ritter, H. Gleiter, and K. Albe, “Deformation behavior of bulk and nanostructured metallic glasses studied via molecular dynamics simulations,” Physical Review B. 2011. link Times cited: 121 Abstract: In this study, we characterize the mechanical properties of … read more Abstract: In this study, we characterize the mechanical properties of Cu64Zr36 nanoglasses under tensile load by means of large-scale molecular dynamics simulations and compare the deformation behavior to the case of a homogeneous bulk glass. The simulations reveal that interfaces act as precursors for the formation of multiple shear bands. In contrast, a bulk metallic glass under uniaxial tension shows inhomogeneous plastic flow confined in one dominant shear band. The results suggest that controlling the microstructure of a nanoglass can pave the way for tuning the mechanical properties of glassy materials. read less J. Fan, “Basics of Atomistic Simulation.” 2010. link Times cited: 1 C. Valencia-Balvín, C. Loyola, J. Osorio-Guillén, and G. Gutiérrez, “Structural and dynamical properties of the Cu46Zr54 alloy in crystalline, amorphous and liquid state: A molecular dynamicstudy,” Physica B-condensed Matter. 2010. link Times cited: 6 B. Arman, S. Luo, T. Germann, and T. Çagin, “Dynamic response of Cu 46 Zr 54 metallic glass to high-strain-rate shock loading: Plasticity, spall, and atomic-level structures,” Physical Review B. 2010. link Times cited: 75 Abstract: We investigate dynamic response of Cu{sub 46}Zr{sub 54} meta… read more Abstract: We investigate dynamic response of Cu{sub 46}Zr{sub 54} metallic glass under adiabatic planar shock wave loading (one-dimensional strain) wjth molecular dynamics simulations, including Hugoniot (shock) states, shock-induced plasticity and spallation. The Hugoniot states are obtained up to 60 CPa along with the von Mises shear flow strengths, and the dynamic spall strength, at different strain rates and temperatures. The spall strengths likely represent the limiting values achievable in experiments such as laser ablation. For the steady shock states, a clear elastic-plastic transition is identified (e.g., in the shock velocity-particle velocity curve), and the shear strength shows strain-softening. However, the elastic-plastic transition across the shock front displays transient stress overshoot (hardening) above the Hugoniot elastic limit followed by a relatively sluggish relaxation to the steady shock state, and the plastic shock front steepens with increasing shock strength. The local von Mises shear strain analysis is used to characterize local deformation, and the Voronoi tessellation analysis, the corresponding short-range structures at various stages of shock, release, tension and spallation. The plasticity in this glass is manifested as localized shear transformation zones and of local structure rather than thermal origin, and void nucleation occurs preferentially at the highly shear-deformed regions. The Voronoi and more » shear strain analyses show that the atoms with different local structures are of different shear resistances that lead to shear localization (e.g., the atoms indexed with (0,0,12,0) are most shear-resistant, and those with (0,2,8,1) are highly prone to shear flow). The dynamic changes in local structures are consistent with the observed deformation dynamics. « less read less M. Li, C. Wang, S. Hao, M. Kramer, and K. Ho, “Structural heterogeneity and medium-range order in Zrsub xCusub 100-x metallic glasses,” Physical Review B. 2009. link Times cited: 189 Abstract: Realistic three-dimensional atomistic structures of Zr{sub x… read more Abstract: Realistic three-dimensional atomistic structures of Zr{sub x}Cu{sub 100-x} (x=35,50) bulk metallic glasses are constructed using a combination of x-ray diffraction experiment and computational modeling. A cluster correlation method is developed to analyze the medium-range order in amorphous systems. We show that the glass systems consist of a stringlike backbone network formed by icosahedral clusters and a liquidlike structure filling in the remaining space. These findings are consistent with those obtained from our independent classical molecular-dynamics studies with embedded-atom method potential for ZrCu system. Such a heterogeneous structure provides a fundamental structural perspective of dynamical heterogeneity and glass formation. read less Q. Cheng, H. Wu, Y. Wang, and X. X. Wang, “Pseudoelasticity of Cu–Zr nanowires via stress-induced martensitic phase transformations,” Applied Physics Letters. 2009. link Times cited: 37 Abstract: Atomistic simulations were performed to investigate the pseu… read more Abstract: Atomistic simulations were performed to investigate the pseudoelastic effects induced by martensitic phase transformation from body-centered cubic (B2) to body-centered tetragonal (BCT) lattice in Cu–Zr nanowires. The phase transformation occurs through nucleation and propagation of {100} twin boundary, which differs from the {101} twin boundary for B2 Ni–Al nanowires. During unloading, extension strain up to 45% can be fully recovered through inverse phase transformation. The BCT lattice has also been verified to be metastable for Cu–Zr nanowires with an energy analysis along the epitaxial Bain path. Our work implies Cu–Zr nanowires may be excellent functional components for nanoelectromechanical systems. read less Y. Cheng, A. Cao, and E. Ma, “Correlation between the elastic modulus and the intrinsic plastic behavior of metallic glasses: The roles of atomic configuration and alloy composition,” Acta Materialia. 2009. link Times cited: 298 D. Zhao, B. Zhu, S. Wang, Y.-T. Niu, L. Xu, and H. Zhao, “Effects of pre-strain on the nanoindentation behaviors of metallic glass studied by molecular dynamics simulations,” Computational Materials Science. 2021. link Times cited: 15 W. Zhao, C. Jialin, and G. Li, “Quantitative analysis of structure evolution of Zr-Cu amorphous alloys caused by cooling rates based on atomic bond proportion,” Computational Materials Science. 2021. link Times cited: 3 A. Chauhan and M. Shukla, “Molecular dynamics simulation of the effect of temperature and size on the mechanical behavior of Cu50Zr50 metallic glass,” Materials Today: Proceedings. 2021. link Times cited: 1 Y. Deng, K. Jiao, and J. Zhang, “Liquid structure evolution of molten iron in blast furnace hearth,” Metallurgical Research & Technology. 2019. link Times cited: 3 Abstract: The iron-carbon interfacial reaction between molten iron and… read more Abstract: The iron-carbon interfacial reaction between molten iron and carbon brick was carried out to simulate the working condition of blast furnace (BF) hearth. The carbon content in molten iron after the reaction was detected to be 5.0% which was almost saturated. XRD and SEM-EDS were conducted on the surface of polished rectangle iron before and after iron-carbon interfacial reaction. Fine striped graphite was observed in iron before iron-carbon interfacial reaction, a large amount of flake-like graphite was observed in iron after iron-carbon interfacial reaction. As a structure-sensitive physical property, the viscosity of molten iron was the macroscopic expression of its liquid structure. The liquid structure of molten iron (Fe-4.5%C, Fe-5.0%C) was measured through a high temperature X-ray diffractometer. The X-ray original diffraction intensity, the structure factor, the pair distribution function, the radial distribution function, and the main parameters of molten iron were obtained through the calculation. The presence of pre-peak in the structure factor indicated that there was a medium-range order in molten iron, some compounds or cluster of atoms might exist in molten iron, the structure model of atoms in liquid Fe-4.5%C was predicted through the structure parameters. The increase of carbon content after iron-carbon interfacial reaction was the essential reason for liquid structure evolution of molten iron in hearth. read less 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 more Abstract: 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 F. Li, H. Zhang, X. Liu, C.-Y. Yu, and Z. Lu, “Effects of cooling rate on the atomic structure of Cu64Zr36 binary metallic glass,” Computational Materials Science. 2018. link Times cited: 25 A. Dutta, “Surface damage of CuZr metallic glass by hypervelocity nano-projectile: A molecular dynamics study,” Computational Materials Science. 2018. link Times cited: 6 N. Yedla and S. Ghosh, “Nature of atomic trajectories and convective flow during plastic deformation of amorphous Cu50Zr50 alloy at room temperature-classical molecular dynamics studies,” Intermetallics. 2017. link Times cited: 15 A. Kumar, P. Gupta, and N. Yedla, “Nanoindentation studies of Zr50Cu50 metallic glass thin film nanocomposites via molecular dynamics simulations,” Revue De Metallurgie-cahiers D Informations Techniques. 2016. link Times cited: 4 Abstract: We carry out molecular dynamics (MD) simulations of nanoinde… read more Abstract: We carry out molecular dynamics (MD) simulations of nanoindentation on Zr50 Cu50 metallic glass thin films (MGTF) containing reinforced nanocrystallites to investigate the shape, size and volume fraction effects on the load-displacement behaviour. We chose spherical (3.2 nm–6.4 nm diameters) and cylindrical (2 nm diameter × 10 nm height) shape nanocrystallites and their volume fraction have been varied in the range of 14%–50%. Nanoindentation tests are conducted at strain rates of 2.5 × 109 s-1 and 2.5 × 1010 s-1 and temperature of 300 K. For comparison of the indentation behaviour; nanoindentation is also carried out on MGTF. It is found that MGTF reinforced with cylindrically shaped nanocrystallites offer much higher yield load than multi-spherical nanocrystallites. Investigations on the effect of crystallite sizes and volume fraction show that single nanocrystallite reinforced MGTF film exhibits the highest maximum load compared to that reinforced with multi-spherical nanocrystallites. With the increase in crystalline volume fraction of the nanocrystallites the MGTFs yield at lesser load. The strain rate greatly affects the material properties. With the increase in strain rate, the load tends to go up. The atomic displacement vector plots reveal nanocrystallites as obstacles to the movement of atoms of the MGTF. read less S. Feng, L. Qi, G. Li, and R. Liu, “Molecular dynamics simulation of structural characterization of elastic and inelastic deformation in ZrCu metallic glasses,” Journal of Nanomaterials. 2014. link Times cited: 8 Abstract: The nanoscopic deformation behaviors in a ZrCu metallic glas… read more Abstract: The nanoscopic deformation behaviors in a ZrCu metallic glass model during loading-unloading process under uniaxial compression have been analyzed on the basis of the molecular dynamics (MD). The reversible degree of shear origin zones (SOZs) is used as the structural indicator to distinguish the elastic deformation and inelastic deformation of ZrCu metallic glass at the atomic level. We find that the formation of SOZs is reversible at the elastic stage but irreversible at the inelastic stage during the loading and unloading processes. At the inelastic stage, the full-icosahedra fraction in SOZs is quickly reduced with increased strain and the decreasing process is also irreversible during the unloading processes. read less K. Koshiyama and K. Shintani, “Atomistic study of the mechanical properties of metallic-glass nanowires,” MRS Proceedings. 2011. link Times cited: 0 Abstract: Melt-growth simulations based on the molecular-dynamics meth… read more Abstract: Melt-growth simulations based on the molecular-dynamics method for both the Cu-Zr and Ni-Al crystalline nanowires of B2 structure are performed to produce metallic-glass nanowires of amorphous structure. Next, tensile deformations of these nanowires are simulated at various temperatures. For the sake of comparison, Cu-Zr and Ni-Al crystalline nanowires of B2 structure are also elongated. It is revealed that the tensile strength of the metallic-glass nanowires is third or fourth of the tensile strength of the crystalline nanowires. Increasing tensile strain, the Cu-Zr crystalline nanowires of B2 structure change their structure twice, whereas the metallic-glass nanowires only decrease their thicknesses locally, and necking takes place. read less R. Forrest, E. Lazar, S. Goel, and J. J. Bean, “Quantifying the differences in properties between polycrystals containing planar and curved grain boundaries,” Nanofabrication. 2022. link Times cited: 0 Abstract: There are several methods in which grain boundaries can be m… read more Abstract: There are several methods in which grain boundaries can be made for modelling, but most produce planar (flat) grains. In this study, we investigated the difference in materials properties between polycrystalline systems comprised of planar grain and curved grain boundaries. Several structural and mechanical properties for both systems were determined. For systems with curved grain boundaries, it was found that the elastic moduli are all larger in magnitude, the excess volumes are comparable, and the plastic properties are smaller. In addition, a grain tracking algorithm was used to determine the differences in the numbers of triple junctions detected between polycrystalline systems with planar and curved grain boundaries. This can be theoretically determined and compared to a simple model system. We find that planar systems of grain boundaries possess significantly more triple junctions than systems of curved grain boundaries by a factor of two. There are also systematic differences between the two types of a system when they undergo grain growth, when there is an anomalous close-packed hexagonal phase which grows in the system of planar grain boundaries. read less N. Amigo, P. Cortés, and F. Valencia, “Research on metallic glasses at the atomic scale: a systematic review,” Sn Applied Sciences. 2022. link Times cited: 1 N. Amigo, “Effect of the atomic construction and preparation procedure on the deformation behaviour of CuZr metallic glasses,” Molecular Simulation. 2021. link Times cited: 2 Abstract: ABSTRACT The construction of metallic glasses (MGs) at the a… read more Abstract: ABSTRACT The construction of metallic glasses (MGs) at the atomic scale for molecular dynamics simulations involves several factors that ultimately affect the deformation behaviour, a matter that has been rarely addressed in the literature. In order to explore this issue, 10 Cu Zr MGs with different random initial arrangements were subjected to compression tests under identical simulation conditions. Three different deformation behaviours were identified: weak shear band (SB) formation + homogeneous nucleation of shear transformation zones (STZs); SB formation + weak STZs nucleation; and heavily localised SB formation. Structural characterisation revealed that samples exhibiting localised SB formation presented larger populations of clusters with a high degree of local five-fold symmetry, fivefold and quasi-fivefold bonding. The deformation behaviour also varied from sample to sample when exploring other parameters such as the initial random velocities and the annealing temperature after replication of the small samples. Therefore, the preparation procedure must be considered cautiously when studying MGs ductility. read less A.-S. Tran, “Control of plastic deformation in Cu50Ta50 metallic glass by insertion of Cu crystalline cores,” Physica Scripta. 2021. link Times cited: 3 Abstract: The tensile characteristics and deformation mechanisms of Cu… read more Abstract: The tensile characteristics and deformation mechanisms of Cu-Ta metallic glasses with the insertion of Cu crystalline cores are investigated using molecular dynamics (MD) simulations. The effects of different Cu crystalline core diameters (D Cu ), experiment temperatures (T), and Cu crystalline core numbers (N) are studied. The results show that the plasticity of the Cu-Ta MGs is significantly improved by inserting Cu crystalline cores. The Shockley dislocations (<112>) make up the majority, and the FCC structures mainly transform into the HCP structures in the Cu crystalline cores. As increasing D Cu , the shear transformation zones (STZs) form more severely, the fraction of atoms with the high shear strain increases, and the tensile strength reduces. As increasing T, the STZs formation is fainter and most intense at 100 K, the fraction of atoms with the shear strain greater than 0.5 (f0.5) and the tensile strength reduce, while the fraction of atoms with the shear strain greater than 0.3 (f0.3) increases. As changing N, the STZs formations in the samples with the N = 2 and 8 are more pronounced, the f0.5 of the samples with the N = 1 and 8 are lower than those in the other cases, and the tensile strength reduces as the N increases. read less C. Kunka, A. Shanker, E. Y. Chen, S. Kalidindi, and R. Dingreville, “Decoding defect statistics from diffractograms via machine learning,” npj Computational Materials. 2021. link Times cited: 6 A. K. A. Lu, K. Nishio, T. Morishita, K. Ohara, Z. Lu, and A. Hirata, “Frank-Kasper Z16 local structures in Cu-Zr metallic glasses,” Physical Review B. 2020. link Times cited: 1 Abstract: Although previous molecular dynamics studies proposed the ex… read more Abstract: Although previous molecular dynamics studies proposed the existence of Zr-centered Frank-Kasper Z16 structures in Cu-Zr metallic glasses, it cannot be concluded yet, owing to the degeneracy problem of the Voronoi index and the artifact in sets of potentials for Cu-Zr systems. We solve both problems by combining a recently developed Finnis-Sinclair potentials to generate realistic atomic structures and the ${p}_{3}$ code to properly differentiate local structures. In previous studies, the Voronoi index $\ensuremath{\langle}0,0,12,4\ensuremath{\rangle}$ was typically associated with Frank-Kasper Z16 local structures. However, we demonstrate that this index includes two types of polyhedra, only one of which is associated with the Frank-Kasper Z16 structures. We reveal that the Z16 structures are more frequent than the other structures and that the two have different behaviors. The tendency of Zr-centered Z16 local structures to be neighbors of Cu-centered icosahedral local structures is also confirmed. Our findings illustrate the importance of properly differentiating local structures in order to elucidate the behavior of metallic glasses at the atomic scale. read less B. Lin, J. Wang, J. Li, and Z. Wang, “A neural-network based framework of developing cross interaction in alloy embedded-atom method potentials: application to Zr–Nb alloy,” Journal of Physics: Condensed Matter. 2020. link Times cited: 2 Abstract: Interaction potentials are critical to molecular dynamics si… read more Abstract: Interaction potentials are critical to molecular dynamics simulations on fundamental mechanisms at atomic scales. Combination of well-developed single-element empirical potentials via cross interaction (CI) is an important and effective way to develop alloy embedded-atom method (EAM) potentials. In this work, based on neural-network (NN) models, firstly we proposed a framework to construct CI potential functions via utilizing single-element potentials. The framework contained four steps: (1) extracting characteristic points from single-element potential functions, (2) constructing CI functions by cubic spline interpolation, (3) evaluating the accuracy of CI functions by referring to first-principle (FP) data, and (4) searching for reasonable CI functions via NN models. Then with this framework, we developed a Zr–Nb alloy CI potential utilizing the MA-III (pure Zr potential developed by Mendelev and Ackland in 2007) and the Fellinger, Park and Wilkins (FPW) (pure Nb potential developed by FPW in 2010) potentials as single-element parts. The calculated results with this Zr–Nb alloy potential showed that: (1) the newly developed CI potential functions could simultaneously present the potential-function features of Zr and Nb; (2) the normalized energy–volume curves of L12 Zr3Nb, B2 ZrNb and L12 ZrNb3 calculated by this CI potential reasonably agreed with FP results; (3) the referred MA-III Zr and FPW Nb potentials can satisfactorily reproduce the priority of prismatic slip in Zr and the tension–compression asymmetry of 〈111〉{112} slip in Nb, while other ab initio developed Zr–Nb alloy potentials cannot. Our study indicates that, this NN based framework can take full advantage of single-element potentials, and is very convenient to develop EAM potentials of alloys; moreover, the new-developed Zr–Nb alloy EAM potential can reasonably describe the complicated deformation behaviors in Zr–Nb systems. read less M. Kramer and M. Li, “Changes in short- and medium-range order in metallic liquids during undercooling,” MRS Bulletin. 2020. link Times cited: 12 Abstract: It has been widely speculated that dominant motifs, such as … read more Abstract: It has been widely speculated that dominant motifs, such as short-range icosahedral order, can influence glass formation and the properties of glasses. Experimental data on both fragile and strong undercooled liquids show corresponding changes in their thermophysical properties consistent with increasing development of a network of interconnect motifs based on molecular dynamics. Describing these regions of local order, how they connect, and how they are related to property changes have been challenging issues, both computationally and experimentally. Yet the consensus is that metallic liquids develop interconnected medium-range order consisting of some regions with lower mobility with deeper undercooling. Less well understood is how these motifs (or “crystal genes”) in the liquid can inhibit nucleation in the deeply undercooled liquid or influence phase selection upon devitrification. These motifs tend to have local packing unlike stable compounds with icosahedral order tending to dominate the best glass formers. The underlying kinetic and thermodynamic forces that guide the formation of these motifs and how they interconnect during undercooling remain open questions. read less M. Sepulveda-Macias, G. Gutiérrez, and F. Lund, “Precursors to plastic failure in a numerical simulation of CuZr metallic glass,” Journal of Physics: Condensed Matter. 2019. link Times cited: 2 Abstract: We deform, in pure shear, a thin sample of Cu50Zr50 metallic… read more Abstract: We deform, in pure shear, a thin sample of Cu50Zr50 metallic glass using a molecular dynamics simulation up to, and including, failure. The experiment is repeated ten times in order to have average values and standard deviations. Although failure occurs at the same value of the externally imposed strain for the ten samples, there is significant sample-to-sample variation in the specific microscopic material behavior. Failure can occur along one, two, or three planes, located at the boundaries of previously formed shear bands (SBs). These SBs form shortly before failure. However, well before their formation and at external strains where plastic deformation just begins to be significant, non-affine displacement organizes itself along localized bands. The SBs subsequently form at the edges of these non-affine-displacement-bands, and present an alternating rotation-quadrupole structure, as found previously by Şopu et al (2017 Phys. Rev. Lett. 119 195503) in the case of a notched sample loaded in tension. The thickness of SBs is roughly determined by the available plastic energy. The onset of shear banding is accompanied by a sharp increase in the rate of change of the rotation angle localization, the strain localization, and the non-affine square displacement. read less R. Jana and L. Pastewka, “Correlations of non-affine displacements in metallic glasses through the yield transition,” Journal of Physics: Materials. 2019. link Times cited: 18 Abstract: We study correlations of non-affine displacements during sim… read more Abstract: We study correlations of non-affine displacements during simple shear deformation of Cu–Zr bulk metallic glasses in molecular dynamics calculations. In the elastic regime, our calculations show exponential correlation with a decay length that we interpret as the size of a shear transformation zone in the elastic regime. This correlation length becomes system-size dependent beyond the yield transition as our calculation develops a shear band, indicative of a diverging length scale. We discuss these observations in the context of a recent proposition of yield as a first-order phase transition. read less B. Bhattarai, R. Thapa, and D. A. Drabold, “Ab initio inversion of structure and the lattice dynamics of a metallic glass: the case of Pd40Ni40P20,” Modelling and Simulation in Materials Science and Engineering. 2019. link Times cited: 2 Abstract: In this paper we infer the structure of Pd40Ni40P20 from exp… read more Abstract: In this paper we infer the structure of Pd40Ni40P20 from experimental diffraction data and ab initio interactions using ‘force enhanced atomic refinement’. Our model accurately reproduces known experimental signatures of the system and is more efficient than conventional melt-quench schemes. We critically evaluate the local order, carry out detailed comparisons to extended x-ray absorption fine structure experiments and also discuss the electronic structure. We thoroughly explore the lattice dynamics of the system, and describe a vibrational localized-to-extended transition and discuss the special role of P dynamics. At low energies P is fully contributing to extended modes, but at higher frequencies executes local motion reminiscent of a ‘rattler’ inside a cage of metal atoms. These highly localized vibrational states suggest a possible utility of these materials for thermoelectric applications. read less J. Yang, Y. Wang, E. Ma, A. Zaccone, L. Dai, and M. Jiang, “Structural Parameter of Orientational Order to Predict the Boson Vibrational Anomaly in Glasses.,” Physical review letters. 2019. link Times cited: 34 Abstract: It has so far remained a major challenge to quantitatively p… read more Abstract: It has so far remained a major challenge to quantitatively predict the boson peak, a THz vibrational anomaly universal for glasses, from features in the amorphous structure. Using molecular dynamics simulations of a model Cu_{50}Zr_{50} glass, we decompose the boson peak to contributions from atoms residing in different types of Voronoi polyhedra. We then introduce a microscopic structural parameter to depict the "orientational order," using the vector pointing from the center atom to the farthest vertex of its Voronoi coordination polyhedron. This order parameter represents the most probable direction of transverse vibration at low frequencies. Its magnitude scales linearly with the boson peak intensity, and its spatial distribution accounts for the quasilocalized modes. This correlation is shown to be universal for different types of glasses. read less R. Christensen, Z. Li, and H. Gao, “An evaluation of the failure modes transition and the Christensen ductile/brittle failure theory using molecular dynamics,” Proceedings of the Royal Society A. 2018. link Times cited: 16 Abstract: The Christensen ductile/brittle failure theory can be interp… read more Abstract: The Christensen ductile/brittle failure theory can be interpreted in terms of the associated failure modes, those of shear bands and voids nucleation. Their conjunction is then termed as the failure modes transition and it is studied here using molecular dynamics. The test material is taken as a particular metallic glass, CuZr. First the theoretical failure criteria are evaluated and then the theoretical failure modes transition is evaluated. Both are found to perform extremely well. The overall failure theory contains three modes of failure, the two already mentioned plus a fracture criterion. A general conclusion from the work is that the voids nucleation criterion is of unusually broad relevance. Voids nucleation leads to voids growth and then further deteriorating mechanisms and ultimately failure. But the voids nucleation is the precipitating event of all that subsequently occurs in this process. Access to these capabilities is gained through the failure theory for all homogeneous, full density, isotropic materials. Only two standard testing measurements are needed to calibrate the entire failure theory, including the transitions. read less J. Feng, J. Feng, P. Chen, and M. Li, “Local shear dominance in equation of state of metallic glass under hydrostatic pressure,” Journal of Applied Physics. 2018. link Times cited: 3 Abstract: Amorphous solids are generally believed to best obey the equ… read more Abstract: Amorphous solids are generally believed to best obey the equation of state derived for homogeneous and isotropic solids under hydrostatic pressure. However, departure from some of the widely accepted theories is observed recently in metallic glasses and no mechanistic explanation is given. Here, we reveal that the underlying cause is the presence of the local internal shear induced by hydrostatic pressure. This subtle phenomenon is difficult to acquire experimentally and is generally ignored in formulating the equation of state. We show that the applied hydrostatic pressure can indeed induce and simultaneously couple to the internal local shear stress that leads to local shear deformation. The internal shear deformation results in a topological transition characterized by a gradual change of the nearest coordination numbers manifested in the deviation in the equation of state. We argue that the reported pressure-shear interaction is a general feature for the class of disordered materials.Amorphous solids are generally believed to best obey the equation of state derived for homogeneous and isotropic solids under hydrostatic pressure. However, departure from some of the widely accepted theories is observed recently in metallic glasses and no mechanistic explanation is given. Here, we reveal that the underlying cause is the presence of the local internal shear induced by hydrostatic pressure. This subtle phenomenon is difficult to acquire experimentally and is generally ignored in formulating the equation of state. We show that the applied hydrostatic pressure can indeed induce and simultaneously couple to the internal local shear stress that leads to local shear deformation. The internal shear deformation results in a topological transition characterized by a gradual change of the nearest coordination numbers manifested in the deviation in the equation of state. We argue that the reported pressure-shear interaction is a general feature for the class of disordered materials. read less W.-R. Jian, L. Wang, X. Yao, and S.-N. Luo, “Balancing strength, hardness and ductility of Cu64Zr36 nanoglasses via embedded nanocrystals,” Nanotechnology. 2018. link Times cited: 20 Abstract: Superplasticity can be achieved in nanoglasses but at the ex… read more Abstract: Superplasticity can be achieved in nanoglasses but at the expense of strength, and such a loss can be mitigated via embedding stronger nanocrystals, i.e., forming nanoglass/nanocrystal composites. As an illustrative case, we investigate plastic deformation of Cu64Zr36 nanoglass/nanocrystalline Cu composites during uniaxial tension and nanoindentation tests with molecular dynamics simulations. With an increasing fraction of nanocrystalline grains, the tensile strength of the composite is enhanced, while its ductility decreases. The dominant interface type changes from a glass–glass interface to glass–crystal interface to grain boundary, corresponding to a failure mode transition from superplastic flow to shear banding to brittle intercrystal fracture, respectively. Accordingly, the indentation hardness increases continuously and strain localization beneath the indenter is more and more severe. For an appropriate fraction of nanocrystalline grains, a good balance among strength, hardness and ductility can be realized, which is useful for the synthesis of novel nanograined glass/crystalline composites with high strength, high hardness and superior ductility. read less S. Alkan and H. Sehitoglu, “Dislocation core effects on slip response of NiTi- a key to understanding shape memory,” International Journal of Plasticity. 2017. link Times cited: 32 K. N. Lad, N. Jakse, and A. Pasturel, “How closely do many-body potentials describe the structure and dynamics of Cu-Zr glass-forming alloy?,” The Journal of chemical physics. 2017. link Times cited: 6 Abstract: Molecular dynamics investigations of the structure and dynam… read more Abstract: Molecular dynamics investigations of the structure and dynamics of Cu64.5Zr35.5 metallic glass-forming alloy have been carried out using five different semi-empirical, many-body interaction potentials based on the Finnis-Sinclair model [M. I. Mendelev et al., J. Appl. Phys. 102, 043501 (2007) (MSK); M. I. Mendelev et al., Philos. Mag. 89, 967 (2009) (MKOSYP); L. Ward et al., e-print arXiv:1209.0619 (2012) (WAFW)] and the embedded-atom model [Y. Q. Cheng et al., Phys. Rev. Lett. 102, 245501 (2009) (CMS) and N. Jakse et al., Phys. Rev. B 85, 174201 (2012) (JNP)]. Although the total static structure factor of the alloy for all the five interaction potentials is, in general, found to be in good agreement with the experimental results, the investigation of a local structure in terms of icosahedral short-range order reveals that the effect of the interaction potential (especially the cohesive part) on the structure of the alloy is not as trivial as it seems. For MSK and JNP potentials, the self-intermediate scattering function Fs(q, t), q-dependence of the structural relaxation time τα in the low-q region, and the self-diffusion coefficient, Ds, for Cu-atoms in the alloy are in excellent agreement with the experimental results. The results for MKOSYP, CMS, and WAFW potentials deviate significantly from the experiment and suggest the dynamics of the alloy to be faster. The difference in the description of the dynamics of the alloy by different potentials is found to be due to the difference in the relevant energy scales corresponding to the temperature scales. τα and Ds exhibit Arrhenius temperature dependence in the high temperature regime above the melting temperature. We also suggest that the attractive forces influence the dynamics of the liquid alloy significantly, which is against the mere perturbative role assigned to the attractive forces in the van der Waals picture of liquids that has been challenged in the recent years. As the five interaction potentials are frequently employed to study thermodynamic, mechanical, and transport properties of Cu-Zr alloys, our study also provides a suitability check for these potentials. read less G. Ren and H. Sehitoglu, “Interatomic potential for the NiTi alloy and its application,” Computational Materials Science. 2016. link Times cited: 45 J. Douglas, B. A. P. Betancourt, X. Tong, and H. Zhang, “Localization model description of diffusion and structural relaxation in glass-forming Cu–Zr alloys,” Journal of Statistical Mechanics: Theory and Experiment. 2016. link Times cited: 56 Abstract: We test the localization model (LM) prediction of a paramete… read more Abstract: We test the localization model (LM) prediction of a parameter-free relationship between the α-structural relaxation time τ α and the Debye–Waller factor 〈u 2 〉 for a series of simulated glass-forming Cu–Zr metallic liquids having a range of alloy compositions. After validating this relationship between the picosecond (‘fast’) and long-time relaxation dynamics over the full range of temperatures and alloy compositions investigated in our simulations, we show that it is also possible to estimate the self-diffusion coefficients of the individual atomic species (D Cu, D Zr) and the average diffusion coefficient D using the LM, in conjunction with the empirical fractional Stokes–Einstein (FSE) relation linking these diffusion coefficients to τ α . We further observe that the fragility and extent of decoupling between D and τ α strongly correlate with 〈u 2 〉 at the onset temperature of glass-formation T A where particle caging and the breakdown of Arrhenius relaxation first emerge. read less X. J. Han, J. G. Li, and H. Schober, “High temperature breakdown of the Stokes-Einstein relation in a computer simulated Cu-Zr melt.,” The Journal of chemical physics. 2016. link Times cited: 29 Abstract: Transport properties and the Stokes-Einstein (SE) relation i… read more Abstract: Transport properties and the Stokes-Einstein (SE) relation in liquid Cu8Zr3 are studied by molecular dynamics simulation with a modified embedded atom potential. The critical temperature Tc of mode coupling theory (MCT) is derived as 930 K from the self-diffusion coefficient D and viscosity η. The SE relation breaks down around TSE = 1900 K, which is far above Tc. At temperatures below TSE, the product of D and η fluctuates around a constant value, similar to the prediction of MCT near Tc. The influence of the microscopic atomic motion on macroscopic properties is investigated by analyzing the time dependent liquid structure and the self-hole filling process. The self-holes for the two components are preferentially filled by atoms of the same component. The self-hole filling dynamics explains the different breakdown behaviors of the SE relation in Zr-rich liquid CuZr2 compared to Cu-rich Cu8Zr3. At TSE, a kink is found in the temperature dependence of both partial and total coordination numbers for the three atomic pair combinations and of the typical time of self-hole filling. This indicates a strong correlation between liquid structure, atomic dynamics, and the breakdown of SE relation. The previously suggested usefulness of the parameter d(D1/D2)/dT to predict TSE is confirmed. Additionally we propose a viscosity criterion to predict TSE in the absence of diffusion data. read less Y. Zhu, G. Liao, T. Shi, M. Li, Z. Tang, and F. Xiong, “Thermoplastic deformation and structural evolutions in nanoimprinting metallic glasses using molecular dynamics analysis,” Journal of Non-crystalline Solids. 2015. link Times cited: 18 J. E. Ludy and T. Rupert, “Amorphous intergranular films act as ultra-efficient point defect sinks during collision cascades,” arXiv: Materials Science. 2015. link Times cited: 24 Q. Zhang, Q. Li, and M. Li, “Chemical segregation in metallic glass nanowires.,” The Journal of chemical physics. 2014. link Times cited: 16 Abstract: Nanowires made of metallic glass have been actively pursued … read more Abstract: Nanowires made of metallic glass have been actively pursued recently due to the superb and unique properties over those of the crystalline materials. The amorphous nanowires are synthesized either at high temperature or via mechanical disruption using focused ion beam. These processes have potential to cause significant changes in structure and chemical concentration, as well as formation of defect or imperfection, but little is known to date about the possibilities and mechanisms. Here, we report chemical segregation to surfaces and its mechanisms in metallic glass nanowires made of binary Cu and Zr elements from molecular dynamics simulation. Strong concentration deviation are found in the nanowires under the conditions similar to these in experiment via focused ion beam processing, hot imprinting, and casting by rapid cooling from liquid state. Our analysis indicates that non-uniform internal stress distribution is a major cause for the chemical segregation, especially at low temperatures. Extension is discussed for this observation to multicomponent metallic glass nanowires as well as the potential applications and side effects of the composition modulation. The finding also points to the possibility of the mechanical-chemical process that may occur in different settings such as fracture, cavitation, and foams where strong internal stress is present in small length scales. read less F. Hussain et al., “Molecular dynamics simulation of mechanical characteristics of CuZr bulk metallic glasses using uni-axial tensile loading technique,” Physica Scripta. 2014. link Times cited: 10 Abstract: In the present study, a three-dimensional molecular dynamics… read more Abstract: In the present study, a three-dimensional molecular dynamics simulation is performed to elaborate the mechanical strength of bulk metallic glasses (BMGs). The radial distribution function (RDF) is used to predict the structural disorder that appeared during the quenching provided for BMGs processing. The mechanical behavior is investigated using uniaxial tensile loading through stress–strain curves. It is observed that during tensile loading, the yield strength of Cu50Zr50 increases with the increase in the strain rate, and it quickly attains the maximum value. Soon after the sample fractures without entering into the plastic region. To elucidate the effects of component concentration, we design BMGs with the following three configurations: Cu25Zr75, Cu50Zr50 and Cu75Zr25. It is revealed from the results that samples with a lower Cu concentration have a higher degree of short-range ordering and lower yield strength, and vice versa. To analyze the significance of crystalline–amorphous interfaces, we designed four cylindrical core–shell nanorods with Cu cores and BMGs shells. It is observed that the mechanical strength of the core–shell nanorod is significantly higher compared to the pure BMGs nanorod. read less H. Gleiter, “Nanoglasses: a new kind of noncrystalline materials,” Beilstein Journal of Nanotechnology. 2013. link Times cited: 99 Abstract: Nanoglasses are a new class of noncrystalline solids. They d… read more Abstract: Nanoglasses are a new class of noncrystalline solids. They differ from today’s glasses due to their microstructure that resembles the microstructure of polycrystals. They consist of regions with a melt-quenched glassy structure connected by interfacial regions, the structure of which is characterized (in comparison to the corresponding melt-quenched glass) by (1) a reduced (up to about 10%) density, (2) a reduced (up to about 20%) number of nearest-neighbor atoms and (3) a different electronic structure. Due to their new kind of atomic and electronic structure, the properties of nanoglasses may be modified by (1) controlling the size of the glassy regions (i.e., the volume fraction of the interfacial regions) and/or (2) by varying their chemical composition. Nanoglasses exhibit new properties, e.g., a Fe90Sc10 nanoglass is (at 300 K) a strong ferromagnet whereas the corresponding melt-quenched glass is paramagnetic. Moreover, nanoglasses were noted to be more ductile, more biocompatible, and catalytically more active than the corresponding melt-quenched glasses. Hence, this new class of noncrystalline materials may open the way to technologies utilizing the new properties. read less S.-H. Wu et al., “Fluctuation between icosahedral and body-centered-cube short-range orders in undercooled Zr liquid,” Journal of Applied Physics. 2011. link Times cited: 14 Abstract: Ab initio molecular dynamics simulations are performed to st… read more Abstract: Ab initio molecular dynamics simulations are performed to study the liquid and undercooled liquid of zirconium. Local structure orders in the liquid at temperatures from 2500 K down to 1830 K are analyzed by using the recently developed cluster alignment method. Our study clearly shows the presence of body-centered-cube (BCC) short-range order in the undercooled liquid in addition to icosahedral order. A strong fluctuation and competition between the short-range icosahedra and BCC orders in the undercooled liquid at 1830 K are also demonstrated from the cluster alignment scheme. read less M. Chassagne, M. Legros, and D. Rodney, “Atomic-scale simulation of screw dislocation/coherent twin boundary interaction in Al, Au, Cu and Ni,” Acta Materialia. 2011. link Times cited: 124 M. Mendelev et al., “Experimental and computer simulation determination of the structural changes occurring through the liquid–glass transition in Cu–Zr alloys,” Philosophical Magazine. 2010. link Times cited: 44 Abstract: Molecular dynamics (MD) simulations were performed of the st… read more Abstract: Molecular dynamics (MD) simulations were performed of the structural changes occurring through the liquid–glass transition in Cu–Zr alloys. The total scattering functions (TSF), and their associated primary diffuse scattering peak positions (K p), heights (K h) and full-widths at half maximum (K FWHM) were used as metrics to compare the simulations to high-energy X-ray scattering data. The residuals of difference between the model and experimental TSFs are ∼0.03 for the liquids and about 0.07 for the glasses. Over the compositional range studied, Zr1− x Cu x (0.1 ≤ x ≤ 0.9), K p, K h and K FWHM show a strong dependence on composition and temperature. The simulation and experimental data correlate well between each other. MD simulation revealed that the Cu–Zr bonds undergo the largest changes during cooling of the liquid, whereas the Cu–Cu bonds change the least. Changes in the partial-pair correlations are more readily seen in the second and third shells. The Voronoi polyhedra (VP) in glasses are dominated by only a few select types that are compositionally dependent. The relative concentrations of the dominant VPs rapidly change in their relative proportion in the deeply undercooled liquid. The experimentally determined region of best glass formability, x Cu ∼ 65%, shows the largest temperature dependent changes for the deeply undercooled liquid in the MD simulation. This region also exhibits very strong temperature dependence for the diffusivity and the total energy of the system. These data point to a strong topological change in the best glass-forming alloys and a concurrent change in the VP chemistry in the deeply undercooled liquid. read less M. Mendelev and M. Kramer, “Reliability of methods of computer simulation of structure of amorphous alloys,” Journal of Applied Physics. 2010. link Times cited: 16 Abstract: We took a model created by the molecular dynamics (MD) simul… read more Abstract: We took a model created by the molecular dynamics (MD) simulation with a semiempirical potential as a target system and explored how its amorphous structure and a few other properties depend on the simulation method. We found that if the cooling rate is too high, 1013–1014 K/s, the system has no time to adjust its structure to the change in temperature/density. Since this cooling corresponds to a typical ab initio MD simulation, this brings into doubt that an equilibrium glass structure can be obtained using ab initio MD simulation. We also used the target partial pair correlation functions (PPCFs) to explore a possibility to create the atomic models from diffraction data alone. We were able to create models with the PPCFs, which nearly coincided with the target ones. Nevertheless, we found that the potential energy of the quenched states and the distribution of the Voronoi polyhedra in the models created from PPCFs were different than the target quantities. This study shows that reverse Monte Carlo techn... read less J. Hwang, A. M. Clausen, H. Cao, and P. Voyles, “Reverse Monte Carlo structural model for a zirconium-based metallic glass incorporating fluctuation microscopy medium-range order data,” Journal of Materials Research. 2009. link Times cited: 24 Abstract: We used reverse Monte Carlo (RMC) modeling to simulate the a… read more Abstract: We used reverse Monte Carlo (RMC) modeling to simulate the atomic structure of a Zr-based bulk metallic glass (BMG), incorporating short-range structural data from the electron diffraction total reduced density function G ( r ) and medium-range structural data from fluctuation electron microscopy (FEM). Including the FEM data created within the model loosely ordered planar atomic arrangements covering regions ∼1 nm in diameter without degrading the agreement with G ( r ). RMC refinement against only G ( r ) produced no agreement with FEM. Improved simulations are needed to create fully realistic BMG structures, but these results show that including FEM in RMC further constrains the structure compared with G ( r ) data alone and that the FEM signal in real materials is likely to arise from pseudo-planar arrangements of atoms. read less M. Mendelev, M. Kramer, R. Ott, D. Sordelet, D. Yagodin, and P. Popel,’ “Development of suitable interatomic potentials for simulation of liquid and amorphous Cu–Zr alloys,” Philosophical Magazine. 2009. link Times cited: 334 Abstract: We present a new semi-empirical potential suitable for molec… read more Abstract: We present a new semi-empirical potential suitable for molecular dynamics simulations of liquid and amorphous Cu–Zr alloys. To provide input data for developing the potential, new experimental measurements of the structure factors for amorphous Cu64.5Zr35.5 alloy were performed. In this work, we propose a new method to include diffraction data in the potential development procedure, which also includes fitting to first-principles and liquid density and enthalpy of mixing data. To refine the new potential, we used first-principles and liquid enthalpy of mixing data published earlier combined with the densities of liquid Cu64.5Zr35.5 measured over a range of temperatures. We show that the potential predicts a liquid-to-glass transition temperature that agrees reasonably well with experimental data. Finally, we compare the new potential with two previously developed semi-empirical potentials for Cu–Zr alloys and examine their comparative and contrasting descriptions of structure and properties for Cu64.5Zr35.5 liquids and glasses. read less M. Mendelev, M. J. Kramer, R. T. Ott, and D. Sordelet, “Molecular dynamics simulation of diffusion in supercooled Cu–Zr alloys,” Philosophical Magazine. 2009. link Times cited: 60 Abstract: Molecular dynamics (MD) simulations of diffusion in Cu–Zr al… read more Abstract: Molecular dynamics (MD) simulations of diffusion in Cu–Zr alloys in their liquid and supercooled liquid states were performed using a recently developed Finnis–Sinclair many-body interatomic potential. To help assess how well the interatomic potential describes the energetics of the Cu–Zr system, the liquid structure determined by MD simulations was compared with wide-angle X-ray scattering measurements of the liquid structure for a Cu64.5Zr35.5 alloy. Diffusion was examined as a function of composition, pressure and temperature. The simulations reveal that the diffusion exhibits strong compositional dependence, with both species exhibiting minimum diffusivities at ∼70% Cu. Moreover, the MD simulations show that the activation volumes for Zr and Cu atoms exhibit a maximum near 70% Cu. Evidence is obtained that the glass transition temperature also changes strongly with composition, thereby contributing to the diffusion behaviour. The relationship between this minimum in diffusion and the apparent best glass-forming composition in the Cu–Zr system is discussed. read less M. Mendelev, R. Ott, M. Heggen, M. Feuerebacher, M. Kramer, and D. Sordelet, “Deformation behavior of an amorphous Cu64.5Zr35.5 alloy: A combined computer simulation and experimental study,” Journal of Applied Physics. 2008. link Times cited: 21 Abstract: Molecular dynamics (MD) simulations were performed to examin… read more Abstract: Molecular dynamics (MD) simulations were performed to examine the temperature-dependent elastic properties and high-temperature deformation behavior of a Cu64.5Zr35.5 amorphous alloy. From the simulations we find that the elastic constants of the amorphous solid and supercooled liquid exhibit an approximately linear temperature dependence. The predicted temperature dependence of the Young’s modulus for the amorphous solid obtained from the MD simulations is in good agreement with experimental measurements using dynamic mechanical analysis. Furthermore, the high-temperature plastic deformation behavior determined by MD simulations is qualitatively in good agreement with results from plastic deformation experiments performed on 1 mm diameter Cu64.5Zr35.5 metallic glass rods at 698 K. Notably, the MD simulations reveal that the flow softening regime of the stress-strain curve corresponds to an increase in the free volume in the atomic structure. Moreover, the simulations indicate that the atomic mobility sig... read less Y. Hu et al., “Atomic scale study of stress-induced misaligned subsurface layers in KDP crystals,” Scientific Reports. 2019. link Times cited: 6 Y. Hu, J. Schuler, and T. Rupert, “Identifying interatomic potentials for the accurate modeling of interfacial segregation and structural transitions,” Computational Materials Science. 2017. link Times cited: 16 S. Liu, S. Liu, F.-gen Li, M. Li, and W.-Q. Wang, “Structural and dynamical characteristics of flow units in metallic glasses,” Scientific Reports. 2017. link Times cited: 8 W. B. Zhang et al., “Size effect on atomic structure in low-dimensional Cu-Zr amorphous systems,” Scientific Reports. 2017. link Times cited: 12 Z. W. Wu, M. Li, W. Wang, and K. Liu, “Hidden topological order and its correlation with glass-forming ability in metallic glasses,” Nature Communications. 2015. link Times cited: 111 D. Rodney, A. Tanguy, and D. Vandembroucq, “Modeling the mechanics of amorphous solids at different length scale and time scale,” Modelling and Simulation in Materials Science and Engineering*. 2011. link Times cited: 244 Abstract: We review the recent literature on the simulation of the str… read more Abstract: We review the recent literature on the simulation of the structure and deformation of amorphous solids, including oxide and metallic glasses. We consider simulations at different length scale and time scale. At the nanometer scale, we review studies based on atomistic simulations, with a particular emphasis on the role of the potential energy landscape and of the temperature. At the micrometer scale, we present the different mesoscopic models of amorphous plasticity and show the relation between shear banding and the type of disorder and correlations (e.g. elastic) included in the models. At the macroscopic range, we review the different constitutive laws used in finite-element simulations. We end with a critical discussion on the opportunities and challenges offered by multiscale modeling and information transfer between scales to study amorphous plasticity. read less
Funding	Not available

Short KIM ID The unique KIM identifier code.	MO_120596890176_005
Extended KIM ID The long form of the KIM ID including a human readable prefix (100 characters max), two underscores, and the Short KIM ID. Extended KIM IDs can only contain alpha-numeric characters (letters and digits) and underscores and must begin with a letter.	EAM_Dynamo_MendelevSordeletKramer_2007_CuZr__MO_120596890176_005
DOI	10.25950/8556dbaf https://doi.org/10.25950/8556dbaf https://commons.datacite.org/doi.org/10.25950/8556dbaf
KIM Item Type Specifies whether this is a Portable Model (software implementation of an interatomic model); Portable Model with parameter file (parameter file to be read in by a Model Driver); Model Driver (software implementation of an interatomic model that reads in parameters).	Portable Model using Model Driver EAM_Dynamo__MD_120291908751_005
Driver	EAM_Dynamo__MD_120291908751_005
KIM API Version	2.0
Potential Type	eam
Programming Language(s) The programming languages used in the code and the percentage of the code written in each one. "N/A" means "not applicable" and refers to model parameterizations which only include parameter tables and have no programming language.	N/A

Previous Version	EAM_Dynamo_MendelevSordeletKramer_2007_CuZr__MO_120596890176_004

Verification Check Dashboard

(Click here to learn more about Verification Checks)

Grade	Name	Category	Brief Description	Full Results	Aux File(s)
P All elements claimed by model are supported in at least one of the tested configurations.	vc-species-supported-as-stated	mandatory	The model supports all species it claims to support; see full description.	Results	Files
P Periodic boundary conditions were correctly supported for all configurations that the model was able to compute.	vc-periodicity-support	mandatory	Periodic boundary conditions are handled correctly; see full description.	Results	Files
P Model energy has permutation symmetry for all configurations the model was able to compute.	vc-permutation-symmetry	mandatory	Total energy and forces are unchanged when swapping atoms of the same species; see full description.	Results	Files
B The letter grade B was assigned because the normalized error in the computation was 5.39574e-08 compared with a machine precision of 2.22045e-16. The letter grade was based on 'score=log10(error/eps)', with ranges A=[0, 7.5], B=(7.5, 10.0], C=(10.0, 12.5], D=(12.5, 15.0), F>15.0. 'A' is the best grade, and 'F' indicates failure.	vc-forces-numerical-derivative	consistency	Forces computed by the model agree with numerical derivatives of the energy; see full description.	Results	Files
P The model is C^1 continuous. This means that the model has continuous energy and continuous first derivative.	vc-dimer-continuity-c1	informational	The energy versus separation relation of a pair of atoms is C1 continuous (i.e. the function and its first derivative are continuous); see full description.	Results	Files
P Model energy and forces are invariant with respect to rigid-body motion (translation and rotation) for all configurations the model was able to compute.	vc-objectivity	informational	Total energy is unchanged and forces transform correctly under rigid-body translation and rotation; see full description.	Results	Files
P Model energy has inversion symmetry for all configurations the model was able to compute.	vc-inversion-symmetry	informational	Total energy is unchanged and forces change sign when inverting a configuration through the origin; see full description.	Results	Files
N/A Unable to perform verification check due to an error.	vc-memory-leak	informational	The model code does not have memory leaks (i.e. it releases all allocated memory at the end); see full description.	Results	Files
P All threads give identical results for tested case. Model appears to be thread-safe.	vc-thread-safe	mandatory	The model returns the same energy and forces when computed in serial and when using parallel threads for a set of configurations. Note that this is not a guarantee of thread safety; see full description.	Results	Files
P Unit conversion successful	vc-unit-conversion	mandatory	The model is able to correctly convert its energy and/or forces to different unit sets; see full description.	Results	Files

This bar chart plot shows the mono-atomic body-centered cubic (bcc) lattice constant predicted by the current model (shown in the unique color) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Cu

Species: Zr

Cohesive Energy Graph

This graph shows the cohesive energy versus volume-per-atom for the current mode for four mono-atomic cubic phases (body-centered cubic (bcc), face-centered cubic (fcc), simple cubic (sc), and diamond). The curve with the lowest minimum is the ground state of the crystal if stable. (The crystal structure is enforced in these calculations, so the phase may not be stable.) Graphs are generated for each species supported by the model.

Species: Zr

Species: Cu

Diamond Lattice Constant

This bar chart plot shows the mono-atomic face-centered diamond lattice constant predicted by the current model (shown in the unique color) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Cu

Species: Zr

Dislocation Core Energies

This graph shows the dislocation core energy of a cubic crystal at zero temperature and pressure for a specific set of dislocation core cutoff radii. After obtaining the total energy of the system from conjugate gradient minimizations, non-singular, isotropic and anisotropic elasticity are applied to obtain the dislocation core energy for each of these supercells with different dipole distances. Graphs are generated for each species supported by the model.

(No matching species)

FCC Elastic Constants

This bar chart plot shows the mono-atomic face-centered cubic (fcc) elastic constants predicted by the current model (shown in blue) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Zr

Species: Cu

FCC Lattice Constant

This bar chart plot shows the mono-atomic face-centered cubic (fcc) lattice constant predicted by the current model (shown in red) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Zr

Species: Cu

FCC Stacking Fault Energies

This bar chart plot shows the intrinsic and extrinsic stacking fault energies as well as the unstable stacking and unstable twinning energies for face-centered cubic (fcc) predicted by the current model (shown in blue) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Cu

FCC Surface Energies

This bar chart plot shows the mono-atomic face-centered cubic (fcc) relaxed surface energies predicted by the current model (shown in blue) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Cu

SC Lattice Constant

This bar chart plot shows the mono-atomic simple cubic (sc) lattice constant predicted by the current model (shown in the unique color) compared with the predictions for all other models in the OpenKIM Repository that support the species. The vertical bars show the average and standard deviation (one sigma) bounds for all model predictions. Graphs are generated for each species supported by the model.

Species: Cu

Species: Zr

Cubic Crystal Basic Properties Table

Species: Cu

Species: Zr

Tests

Disclaimer From Model Developer

The authors note in the paper that this potential was never intended for serious simulation. An improved Cu-Zr model can be found in KIM item https://openkim.org/id/MO_609260676108_000.

CohesiveEnergyVsLatticeConstant__TD_554653289799_003

Cohesive energy versus lattice constant curve for monoatomic cubic lattices v003

Creators:
Contributor: karls
Publication Year: 2019
DOI: https://doi.org/10.25950/64cb38c5

This Test Driver uses LAMMPS to compute the cohesive energy of a given monoatomic cubic lattice (fcc, bcc, sc, or diamond) at a variety of lattice spacings. The lattice spacings range from a_min (=a_min_frac*a_0) to a_max (=a_max_frac*a_0) where a_0, a_min_frac, and a_max_frac are read from stdin (a_0 is typically approximately equal to the equilibrium lattice constant). The precise scaling and number of lattice spacings sampled between a_min and a_0 (a_0 and a_max) is specified by two additional parameters passed from stdin: N_lower and samplespacing_lower (N_upper and samplespacing_upper). Please see README.txt for further details.

Test	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Cohesive energy versus lattice constant curve for bcc Cu v004	view	14829
Cohesive energy versus lattice constant curve for bcc Zr v004	view	12283
Cohesive energy versus lattice constant curve for diamond Cu v004	view	21208
Cohesive energy versus lattice constant curve for diamond Zr v004	view	12999
Cohesive energy versus lattice constant curve for fcc Cu v004	view	13835
Cohesive energy versus lattice constant curve for fcc Zr v004	view	12482
Cohesive energy versus lattice constant curve for sc Cu v004	view	19456
Cohesive energy versus lattice constant curve for sc Zr v004	view	13865

ElasticConstantsCrystal__TD_034002468289_000

Elastic constants for arbitrary crystals at zero temperature and pressure v000

Creators:
Contributor: ilia
Publication Year: 2024
DOI: https://doi.org/10.25950/888f9943

Computes the elastic constants for an arbitrary crystal. A robust computational protocol is used, attempting multiple methods and step sizes to achieve an acceptably low error in numerical differentiation and deviation from material symmetry. The crystal structure is specified using the AFLOW prototype designation as part of the Crystal Genome testing framework. In addition, the distance from the obtained elasticity tensor to the nearest isotropic tensor is computed.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Elastic constants for CuZr in AFLOW crystal prototype A10B7_oC68_64_f2g_adef at zero temperature and pressure v000		view	259871

ElasticConstantsCubic__TD_011862047401_006

Elastic constants for cubic crystals at zero temperature and pressure v006

Creators: Junhao Li and Ellad Tadmor
Contributor: tadmor
Publication Year: 2019
DOI: https://doi.org/10.25950/5853fb8f

Computes the cubic elastic constants for some common crystal types (fcc, bcc, sc, diamond) by calculating the hessian of the energy density with respect to strain. An estimate of the error associated with the numerical differentiation performed is reported.

Test	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Elastic constants for bcc Cu at zero temperature v006	view	2047
Elastic constants for bcc Zr at zero temperature v006	view	6398
Elastic constants for diamond Cu at zero temperature v001	view	6366
Elastic constants for diamond Zr at zero temperature v001	view	11580
Elastic constants for fcc Cu at zero temperature v006	view	2367
Elastic constants for fcc Zr at zero temperature v006	view	2015
Elastic constants for sc Cu at zero temperature v006	view	1887
Elastic constants for sc Zr at zero temperature v006	view	6526

ElasticConstantsHexagonal__TD_612503193866_004

Elastic constants for hexagonal crystals at zero temperature v004

Creators: Junhao Li
Contributor: jl2922
Publication Year: 2019
DOI: https://doi.org/10.25950/d794c746

Computes the elastic constants for hcp crystals by calculating the hessian of the energy density with respect to strain. An estimate of the error associated with the numerical differentiation performed is reported.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Elastic constants for hcp Cu at zero temperature v004		view	2260
Elastic constants for hcp Zr at zero temperature v004		view	1942

EquilibriumCrystalStructure__TD_457028483760_001

Equilibrium structure and energy for a crystal structure at zero temperature and pressure v001

Creators:
Contributor: ilia
Publication Year: 2023
DOI: https://doi.org/10.25950/e8a7ed84

Computes the equilibrium crystal structure and energy for an arbitrary crystal at zero temperature and applied stress by performing symmetry-constrained relaxation. The crystal structure is specified using the AFLOW prototype designation. Multiple sets of free parameters corresponding to the crystal prototype may be specified as initial guesses for structure optimization. No guarantee is made regarding the stability of computed equilibria, nor that any are the ground state.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Equilibrium crystal structure and energy for Cu in AFLOW crystal prototype A_cF4_225_a v001		view	83265
Equilibrium crystal structure and energy for Cu in AFLOW crystal prototype A_cI2_229_a v001		view	73547

EquilibriumCrystalStructure__TD_457028483760_002

Equilibrium structure and energy for a crystal structure at zero temperature and pressure v002

Creators:
Contributor: ilia
Publication Year: 2024
DOI: https://doi.org/10.25950/2f2c4ad3

Computes the equilibrium crystal structure and energy for an arbitrary crystal at zero temperature and applied stress by performing symmetry-constrained relaxation. The crystal structure is specified using the AFLOW prototype designation. Multiple sets of free parameters corresponding to the crystal prototype may be specified as initial guesses for structure optimization. No guarantee is made regarding the stability of computed equilibria, nor that any are the ground state.

Test	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype A5B_cF24_216_ae_c v002	view	152983
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB2_cF96_227_e_cf v002	view	769629
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB2_tI6_139_a_e v002	view	44294
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB_cP2_221_a_b v002	view	88786
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB_mC16_8_2ab_2ab v002	view	85621
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB_oC8_63_c_c v002	view	45084

EquilibriumCrystalStructure__TD_457028483760_003

Equilibrium structure and energy for a crystal structure at zero temperature and pressure v003

Creators:
Contributor: ilia
Publication Year: 2025
DOI: https://doi.org/10.25950/866c7cfa

Computes the equilibrium crystal structure and energy for an arbitrary crystal at zero temperature and applied stress by performing symmetry-constrained relaxation. The crystal structure is specified using the AFLOW prototype designation. Multiple sets of free parameters corresponding to the crystal prototype may be specified as initial guesses for structure optimization. No guarantee is made regarding the stability of computed equilibria, nor that any are the ground state.

Test	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype A10B7_oC68_64_f2g_adef v003	view	593240
Equilibrium crystal structure and energy for Zr in AFLOW crystal prototype A_cF4_225_a v003	view	143151
Equilibrium crystal structure and energy for Zr in AFLOW crystal prototype A_cI2_229_a v003	view	135981
Equilibrium crystal structure and energy for Zr in AFLOW crystal prototype A_hP2_194_c v003	view	139870

GrainBoundaryCubicCrystalSymmetricTiltRelaxedEnergyVsAngle__TD_410381120771_003

Relaxed energy as a function of tilt angle for a symmetric tilt grain boundary within a cubic crystal v003

Creators:
Contributor: brunnels
Publication Year: 2022
DOI: https://doi.org/10.25950/2c59c9d6

Computes grain boundary energy for a range of tilt angles given a crystal structure, tilt axis, and material.

Test	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Relaxed energy as a function of tilt angle for a 100 symmetric tilt grain boundary in fcc Cu v001	view	10375379
Relaxed energy as a function of tilt angle for a 110 symmetric tilt grain boundary in fcc Cu v001	view	56557017
Relaxed energy as a function of tilt angle for a 111 symmetric tilt grain boundary in fcc Cu v001	view	30189425
Relaxed energy as a function of tilt angle for a 112 symmetric tilt grain boundary in fcc Cu v001	view	108698943

LatticeConstantCubicEnergy__TD_475411767977_007

Equilibrium lattice constant and cohesive energy of a cubic lattice at zero temperature and pressure v007

Creators: Daniel S. Karls and Junhao Li
Contributor: karls
Publication Year: 2019
DOI: https://doi.org/10.25950/2765e3bf

Equilibrium lattice constant and cohesive energy of a cubic lattice at zero temperature and pressure.

Test	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Equilibrium zero-temperature lattice constant for bcc Cu v007	view	2495
Equilibrium zero-temperature lattice constant for bcc Zr v007	view	2399
Equilibrium zero-temperature lattice constant for diamond Cu v007	view	3263
Equilibrium zero-temperature lattice constant for diamond Zr v007	view	4606
Equilibrium zero-temperature lattice constant for fcc Cu v007	view	4223
Equilibrium zero-temperature lattice constant for fcc Zr v007	view	2751
Equilibrium zero-temperature lattice constant for sc Cu v007	view	2335
Equilibrium zero-temperature lattice constant for sc Zr v007	view	2335

LatticeConstantHexagonalEnergy__TD_942334626465_005

Equilibrium lattice constants for hexagonal bulk structures at zero temperature and pressure v005

Creators: Daniel S. Karls and Junhao Li
Contributor: karls
Publication Year: 2019
DOI: https://doi.org/10.25950/c339ca32

Calculates lattice constant of hexagonal bulk structures at zero temperature and pressure by using simplex minimization to minimize the potential energy.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Equilibrium lattice constants for hcp Cu v005		view	53389
Equilibrium lattice constants for hcp Zr v005		view	23177

LinearThermalExpansionCoeffCubic__TD_522633393614_001

Linear thermal expansion coefficient of cubic crystal structures v001

Creators: Mingjian Wen
Contributor: mjwen
Publication Year: 2019
DOI: https://doi.org/10.25950/fc69d82d

This Test Driver uses LAMMPS to compute the linear thermal expansion coefficient at a finite temperature under a given pressure for a cubic lattice (fcc, bcc, sc, diamond) of a single given species.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Linear thermal expansion coefficient of fcc Cu at 293.15 K under a pressure of 0 MPa v001		view	13562216

PhononDispersionCurve__TD_530195868545_004

Phonon dispersion relations for an fcc lattice v004

Creators: Matt Bierbaum
Contributor: mattbierbaum
Publication Year: 2019
DOI: https://doi.org/10.25950/64f4999b

Calculates the phonon dispersion relations for fcc lattices and records the results as curves.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Phonon dispersion relations for fcc Cu v004		view	52846

StackingFaultFccCrystal__TD_228501831190_002

Stacking and twinning fault energies of an fcc lattice at zero temperature and pressure v002

Creators:
Contributor: SubrahmanyamPattamatta
Publication Year: 2019
DOI: https://doi.org/10.25950/b4cfaf9a

Intrinsic and extrinsic stacking fault energies, unstable stacking fault energy, unstable twinning energy, stacking fault energy as a function of fractional displacement, and gamma surface for a monoatomic FCC lattice at zero temperature and pressure.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Stacking and twinning fault energies for fcc Cu v002		view	13553803

SurfaceEnergyCubicCrystalBrokenBondFit__TD_955413365818_004

High-symmetry surface energies in cubic lattices and broken bond model v004

Creators: Matt Bierbaum
Contributor: mattbierbaum
Publication Year: 2019
DOI: https://doi.org/10.25950/6c43a4e6

Calculates the surface energy of several high symmetry surfaces and produces a broken-bond model fit. In latex form, the fit equations are given by:

E_{FCC} (\vec{n}) = p_1 (4 \left( |x+y| + |x-y| + |x+z| + |x-z| + |z+y| +|z-y|\right)) + p_2 (8 \left( |x| + |y| + |z|\right)) + p_3 (2 ( |x+ 2y + z| + |x+2y-z| + |x-2y + z| + |x-2y-z| + |2x+y+z| + |2x+y-z| +|2x-y+z| +|2x-y-z| +|x+y+2z| +|x+y-2z| +|x-y+2z| +|x-y-2z| ) + c

E_{BCC} (\vec{n}) = p_1 (6 \left( | x+y+z| + |x+y-z| + |-x+y-z| + |x-y+z| \right)) + p_2 (8 \left( |x| + |y| + |z|\right)) + p_3 (4 \left( |x+y| + |x-y| + |x+z| + |x-z| + |z+y| +|z-y|\right)) +c.

In Python, these two fits take the following form:

def BrokenBondFCC(params, index):

import numpy
x, y, z = index
x = x / numpy.sqrt(x**2.+y**2.+z**2.)
y = y / numpy.sqrt(x**2.+y**2.+z**2.)
z = z / numpy.sqrt(x**2.+y**2.+z**2.)

return params[0]*4* (abs(x+y) + abs(x-y) + abs(x+z) + abs(x-z) + abs(z+y) + abs(z-y)) + params[1]*8*(abs(x) + abs(y) + abs(z)) + params[2]*(abs(x+2*y+z) + abs(x+2*y-z) +abs(x-2*y+z) +abs(x-2*y-z) + abs(2*x+y+z) +abs(2*x+y-z) +abs(2*x-y+z) +abs(2*x-y-z) + abs(x+y+2*z) +abs(x+y-2*z) +abs(x-y+2*z) +abs(x-y-2*z))+params[3]

def BrokenBondBCC(params, x, y, z):

import numpy
x, y, z = index
x = x / numpy.sqrt(x**2.+y**2.+z**2.)
y = y / numpy.sqrt(x**2.+y**2.+z**2.)
z = z / numpy.sqrt(x**2.+y**2.+z**2.)

return params[0]*6*(abs(x+y+z) + abs(x-y-z) + abs(x-y+z) + abs(x+y-z)) + params[1]*8*(abs(x) + abs(y) + abs(z)) + params[2]*4* (abs(x+y) + abs(x-y) + abs(x+z) + abs(x-z) + abs(z+y) + abs(z-y)) + params[3]

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Broken-bond fit of high-symmetry surface energies in fcc Cu v004		view	39538

VacancyFormationEnergyRelaxationVolume__TD_647413317626_001

Monovacancy formation energy and relaxation volume for cubic and hcp monoatomic crystals v001

Creators:
Contributor: efuem
Publication Year: 2023
DOI: https://doi.org/10.25950/fca89cea

Computes the monovacancy formation energy and relaxation volume for cubic and hcp monoatomic crystals.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Monovacancy formation energy and relaxation volume for fcc Cu		view	700057
Monovacancy formation energy and relaxation volume for hcp Zr		view	402115

VacancyFormationMigration__TD_554849987965_001

Vacancy formation and migration energies for cubic and hcp monoatomic crystals v001

Creators:
Contributor: efuem
Publication Year: 2023
DOI: https://doi.org/10.25950/c27ba3cd

Computes the monovacancy formation and migration energies for cubic and hcp monoatomic crystals.

Test	Test Results	Link to Test Results page	Benchmark time Usertime multiplied by the Whetstone Benchmark. This number can be used (approximately) to compare the performance of different models independently of the architecture on which the test was run. Measured in Millions of Whetstone Instructions (MWI)
Vacancy formation and migration energy for fcc Cu		view	2799714
Vacancy formation and migration energy for hcp Zr		view	2681406

Errors

ElasticConstantsCrystal__TD_034002468289_000

Test	Error Categories	Link to Error page
Elastic constants for CuZr in AFLOW crystal prototype A10B7_oC68_64_f2g_adef at zero temperature and pressure v000	other	view

EquilibriumCrystalStructure__TD_457028483760_002

Test	Error Categories	Link to Error page
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB3_tP4_123_a_ce v002	other	view
Equilibrium crystal structure and energy for CuZr in AFLOW crystal prototype AB_mP4_11_e_e v002	other	view

LatticeConstantCubicEnergy__TD_475411767977_006

Test	Error Categories	Link to Error page
Equilibrium zero-temperature lattice constant for bcc Zr	other	view

LatticeConstantHexagonalEnergy__TD_942334626465_004

Test	Error Categories	Link to Error page
Equilibrium lattice constants for hcp Zr	other	view

No Driver

Verification Check	Error Categories	Link to Error page
DimerContinuityC1__VC_303890932454_005	other	view

Files

CMakeLists.txt
Cu-Zr.eam.fs
LICENSE.CDDL
kimprovenance.edn
kimspec.edn

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EAM_Dynamo_MendelevSordeletKramer_2007_CuZr__MO_120596890176_005.txz	Tar+XZ	Linux and OS X archive
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This Model requires a Model Driver. Archives for the Model Driver EAM_Dynamo__MD_120291908751_005 appear below.

EAM_Dynamo__MD_120291908751_005.txz	Tar+XZ	Linux and OS X archive
EAM_Dynamo__MD_120291908751_005.zip	Zip	Windows archive

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EAM_Dynamo_MendelevSordeletKramer_2007_CuZr__MO_120596890176_005

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Visualizers (in-page)

BCC Lattice Constant

Cohesive Energy Graph

Diamond Lattice Constant

Dislocation Core Energies

FCC Elastic Constants

FCC Lattice Constant

FCC Stacking Fault Energies

FCC Surface Energies

SC Lattice Constant

Cubic Crystal Basic Properties Table

Tests

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Errors

Files

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