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Modeling Extensive Defects in Metals through Classical Potential-Guided Sampling and Automated Configuration Reconstruction

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arXiv 2024年

作者： Shuang, Fei Liu, Kai Ji, Yucheng Gao, Wei Laurenti, Luca Dey, Poulumi Department of Materials Science and Engineering Faculty of Mechanical Engineering Delft University of Technology Mekelweg 2 Delft2628 CD Netherlands Beijing Advanced Innovation Center for Materials Genome Engineering National Materials Corrosion and Protection Data Center Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China J. Mike Walker’66 Department of Mechanical Engineering Texas A&M University College StationTX77843 United States Department of Materials Science & Engineering Texas A&M University College StationTX77843 United States Faculty of Mechanical Engineering Delft University of Technology Mekelweg 2 Delft2628 CD Netherlands

Extended defects such as dislocation networks and general grain boundaries are ubiquitous in metals, and accurately modeling these extensive defects is crucial for understanding their deformation mechanisms. Existing machine learning interatomic potentials (MLIPs) often fall short in adequately describing these defects, as their significant characteristic sizes exceed the computational limits of first-principles calculations. In this study, we address these challenges by establishing a comprehensive defect genome through empirical interatomic potential-guided sampling. To further enable accurate first-principles calculations on this defect genome, we have developed an automated configuration reconstruction technique. This method transforms defect atomic clusters into periodic configurations through precise atom insertion, utilizing Grand Canonical Monte Carlo simulations. These strategies enable the development of highly accurate and transferable MLIPs for modeling extensive defects in metals. Using body-centered cubic tungsten as a model system, we develop an MLIP that reveals unique plastic mechanisms in simulations of nanoindentation. This framework not only improves the modeling accuracy of extensive defects in crystalline materials but also establishes a robust foundation for further advancement of MLIP development through the strategic use of defect genomes. Copyright © 2024, The Authors. All rights reserved.

关键词： Crystalline materials

Cr-modified CuAlBe shape memory alloy: Role of microstructure, thermodynamic parameters, superelasticity, dissipated energy and corrosion resistance

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Journal of Alloys and Metallurgical Systems

Journal of Alloys and Metallurgical Systems 2024年 7卷

作者： Silva, David D.S. Candido, Gemierson V.M. Alves, Ricardo F. Dias, Elisabeth A.M.G.S. Oliveira, Danniel F. Federal University of São Carlos Graduate Program in Materials Science and Engineering SP São Carlos13565-905 Brazil Colorado School of Mines George S. Ansell Department of Metallurgical and Materials Engineering GoldenCO80401 United States Federal University of Paraíba Graduate Program in Mechanical Engineering PB João Pessoa58051-900 Brazil Federal University of Rio Grande do Norte Graduate Program in Materials Science and Engineering RN Natal59078-970 Brazil Federal University of Paraíba Graduate Program in Materials Science and Engineering PB João Pessoa58051-900 Brazil

This study reports the effects of Cr addition on the microstructure, superelasticity and corrosion resistance improvement of CuAlBe shape memory alloy. Analysis via structural, morphological, thermal, mechanical and electrochemical characterizations were performed. The analyses revealed austenite as the stable phase at room temperature for all samples. The increase in the Cr content caused a slight increase in the recovery rate and dissipated energy. Electrochemical results demonstrate that a small addition of Cr (0.1–0.3 wt%) increase the corrosion resistance due the decreases of the corrosion current density and increase of the corrosion potential. © 2024 The Authors

关键词： Corrosion resistance

Evaluation of Solubilization Time in Uncontrolled Atmosphere on Grain Growth, Phase Transformation Temperatures, and mechanical Properties in a CuAlBe SMA

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Metallurgical and materials Transactions A: Physical Metallurgy and materials science 2025年

作者： da Silva Franco, Luiz Henrique Caluête, Rafael Evaristo de Lima, Bruno Alessandro Silva Guedes de Oliveira, Danniel Ferreira Brito, Ieverton Caiandre Andrade Department of Materials Engineering Federal University of Paraíba PB João Pessoa58051-900 Brazil Department of Mechanical Engineering Federal University of Paraíba PB João Pessoa58051-900 Brazil Graduate Program in Materials Science and Engineering Federal University of Paraíba PB João Pessoa58051-900 Brazil

Thermomechanical properties of SMAs are strongly affected by the metallurgical conditions imposed during their production. In this work, experiments were performed to investigate the behavior of the Cu–11.8Al–0.50Be (wt pct) SMA during solubilization at different times under an uncontrolled atmosphere. The results presented serve as a basis for predicting the macrostructure and thermomechanical properties in practical applications using CuAlBe SMAs. The grain growth evaluated by OM proved to be extremely sensitive to treatment time even after short intervals, tending to stabilize after 12 hours. Chemical analysis by EDS indicated a small variation in Al content produced during solidification, with 3 hours being enough to homogenize the Al concentration throughout the ingot despite producing a microstructure with non-uniform grain size. This variation in Al is not significant enough to influence the phase transformation temperatures, with the changes attributed to the grain growth and loss of Be by oxidation. ¼ hour resulted in the lowest values for maximum stress/strain, while 24 hours of solubilization showed the highest values of strain with small dispersion. The mixed fracture type (brittle/ductile) observed by SEM in the ¼ hour samples supports the hypothesis that ¼ hour is insufficient to dissolve the phases formed during solidification. This effect is aggravated by the strong elastic anisotropy, which contributes to embrittlement during quenching. © The Minerals, Metals & materials Society and ASM International 2025.

关键词： Setting

Decoding the Hidden Dynamics of Super-Arrhenius Hydrogen Diffusion in Multi-Principal Element Alloys via Machine Learning

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arXiv 2024年

作者： Shuang, Fei Ji, Yucheng Wei, Zixiong Dong, Chaofang Gao, Wei Laurenti, Luca Dey, Poulumi Department of Materials Science and Engineering Faculty of Mechanical Engineering Delft University of Technology Mekelweg 2 Delft2628 CD Netherlands Beijing Advanced Innovation Center for Materials Genome Engineering National Materials Corrosion and Protection Data Center Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China J. Mike Walker'66 Department of Mechanical Engineering Texas A&M University College StationTX77843 United States Department of Materials Science & Engineering Texas A&M University College StationTX77843 United States Faculty of Mechanical Engineering Delft University of Technology Mekelweg 2 Delft2628 CD Netherlands

Understanding atomic hydrogen (H) diffusion in multi-principal element alloys (MPEAs) is essential for advancing clean energy technologies such as H transport, storage, and nuclear fusion applications. However, the vast compositional space and the intricate chemical environments inherent in MPEAs pose significant obstacles. In this work, we address this challenge by developing a multifaceted machine learning framework that integrates machine-learning force field, neural network-driven kinetic Monte Carlo, and machine-learning symbolic regression. This framework allows for accurate investigation of H diffusion across the entire compositional space of body-centered cubic (BCC) refractory MoNbTaW alloys, achieving density functional theory accuracy. For the first time, we discover that H diffusion in MPEAs exhibits super-Arrhenius behavior, described by the Vogel-Fulcher-Tammann model, where the Vogel temperature correlates with the 5th percentile of H solution energy spectrum. We also derive robust analytical expressions that can be used to predict H diffusivity in general BCC MPEAs. Our findings further elucidate that chemical short-range order (SRO) generally does not impact H diffusion, except it enhances diffusion when "H-favoring" elements (notably Nb and Ta) are present in low concentrations. These findings not only enhance our understanding of H diffusion dynamics in general MPEAs but also guide the development of advanced MPEAs in H-related applications by manipulating element type, composition and SRO. Copyright © 2024, The Authors. All rights reserved.

关键词： Niobium alloys

Reconfiguring Surface Acoustic Wave Microfluidics via In Situ Control of Elastic Wave Polarization

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Physical Review Letters 2025年第3期134卷 037002-037002页

作者： Yu Gao (郜煜) Thomas Voglhuber-Brunnmaier Yuekang Li Leyla Akh Nicholas H. Patino Apresio Kefin Fajrial Massimo Ruzzene Bernhard Jakoby Xiaoyun Ding Paul M. Rady Department of Mechanical Engineering University of Colorado Boulder Colorado 80309 USA Institute for Microelectronics and Microsensors Johannes Kepler University Linz Austria Biomedical Engineering Program University of Colorado Boulder Colorado 80309 USA Materials Science and Engineering Program University of Colorado Boulder Colorado 80309 USA BioFrontiers Institute University of Colorado Boulder Colorado 80309 USA

We demonstrate in situ control of the elastic wave polarization in a surface acoustic wave (SAW). It allows us to create highly reconfigurable SAW microfluidics that can be switched on demand between the acoustohydrodynamic (AHD) regime and electrohydrodynamic (EHD) regime for manipulating particles and cells. The control of wave polarization comes from our experimental and theoretical identification of an unexpected shear-horizontal (SH) wave mode in a conventional Rayleigh (R) wave design, which is stereotyped to excite only vertically polarized Rayleigh SAWs. The SH wave mode is predominantly horizontally polarized and can be selectively excited to propagate in the same direction as the Rayleigh SAW. Such a selective wave generation between the SH mode and R mode allows for reconfiguration between AHD and EHD regimes that leads to unprecedented colloidal patterns and assembly dynamics. Such a reconfiguration of the particle manipulation mechanism can be explained by the controllable competition or synergism between the coexisting acoustic and electric fields. Remarkably, in the EHD regime, a virtual zero-boundary electric quadrupole is created, and a novel colloidal diamond-shaped assembly is observed in this piezoelectric-quadrupole trap, which was rarely reported in acoustic or electric microfluidics. The presented in situ control of polarization revolutionizes our understanding of SAW and acoustofluidics, expands its potential by assuming the advantages of AHD and EHD on demand, and inspires new strategies in micro- and nanoscale manufacturing and manipulation, with applications beyond fundamental scientific interest.

关键词： Microfluidics

Exploring nonlinear Rashba effect and spin Hall conductivity in Janus MXenes W2COX (X = S, Se, Te)

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arXiv 2024年

作者： Bordoloi, Arjyama Singh, Sobhit Department of Mechanical Engineering University of Rochester RochesterNY14627 United States Materials Science Program University of Rochester RochesterNY14627 United States

Rashba spin-orbit coupling (RSOC) facilitates spin manipulation without relying on an external magnetic field, opening up exciting possibilities for advanced spintronic devices. In this work, we examine the effects of crystal momentum (k) nonlinearity and anisotropy on the conventional Rashba effect, with a particular focus on their impact on the spin Hall conductivity (SHC) in a newly predicted family of 2D Janus materials, W2COX (X = S, Se, Te). Using first-principles density functional theory calculations, we confirm the dynamical and mechanical stability of the studied 2D materials. Strikingly, this materials family exhibits pronounced nonlinear Rashba spin splitting at the Γ point of Brillouin zone near the Fermi level, which cannot be adequately described by the linear-k Rashba model. Therefore, third-order momentum contributions (k3) must be incorporated into the Rashba Hamiltonian. Our analysis reveals that among the studied systems, W2COS exhibits the highest k3 contribution of −45.9 eV Å3, despite having the lowest linear Rashba constant. A detailed analysis of electronic structure reveals topological nontrivial behaviour in these 2D materials, yielding sizable SHC that is primarily governed by the nonlinear Rashba effect. Notably, these materials also exhibit large spin Hall angle (0.018-2.5), which is comparable to that of in bulk topological insulators like Bi2Se3 and Bi2Te3, and surpassing those in narrow bandgap bulk semiconductors GeTe and SnTe, as well as heavy metals such as Pt. Sizable SHC, large spin Hall angles, and the ability to tune SHC via electric fields without altering the topological properties, rooted in the crystal field splitting, underscore the potential of these materials for spintronic applications. © 2024, CC BY.

关键词： Spin Hall effect

A mini review on two-dimensional nanomaterial assembly

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Nano Research 2020年第5期13卷 1179-1190页

作者： Zhiwei Fang Qiyu Xing Desiree Fernandez Xiao Zhang Guihua Yu Materials Science and Engineering Program and Department of Mechanical Engineering The University of Texas at AustinAustinTexas 78712USA 2 School of Chemistry and Materials ScienceUniversity of Science&Technology of ChinaHefei 230026China

Two-dimensional(2D)nanomaterials have attracted a great deal of attention since the discovery of graphene in 2004,due to their intriguing physicochemical properties and wide-ranging applications in catalysis,energy-related devices,electronics and *** maximize the potential of 2D nanomaterials for their technological applications,controlled assembly of 2D nanobulding blocks into integrated systems is critically *** mini review summarizes the reported strategies of 2D materials-based assembly into integrated functional nanostructures,from in-situ assembly method to post-synthesis *** applications of 2D assembled integrated structures are also covered,especially in the areas of energy,electronics and sensing,and we conclude with discussion on the remaining challenges and potential directions in this emerging field.

关键词： two-dimensional materials assembly self-assembly post-synthesis assembly integrated nanostructures

Electrochemically Modulated Metasurfaces

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Electrochemically Modulated Metasurfaces

Conference on Lasers and Electro-Optics (CLEO)

作者： Janna Eaves-Rathert Elena Kovalik Chibuzor Fabian Ugwu Cary L. Pint Jason G. Valentine Department of Mechanical Engineering Vanderbilt University Nashville TN USA Interdisciplinary Materials Science Program Vanderbilt University Nashville TN USA Department of Mechanical Engineering Iowa State University Ames IA

Electrochemical intercalation of lithium in titanium dioxide and silicon-based metasurfaces is used to initiate phase changes in a continuously tunable, reversible, and bi-stable manner for dynamic control over struct... 详细信息

ISBN: (纸本)9781957171258

关键词： Absorption coefficient Structural color Surface plasmon polaritons Surface plasmons Thin films Titanium dioxide

First-principles investigation of elastic, vibrational, and thermodynamic properties of kagome metals CsM3Te5 (M = Ti, Zr, Hf)

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arXiv 2024年

作者： Wei, Yifan Bordoloi, Arjyama Chuang, Chaon-En Singh, Sobhit Department of Mechanical Engineering University of Rochester RochesterNY14627 United States Materials Science Program University of Rochester RochesterNY14627 United States

Kagome metals are a unique class of quantum materials characterized by their distinct atomic lattice arrangement, featuring interlocking triangles and expansive hexagonal voids. These lattice structures impart exotic properties, including superconductivity, interaction-driven topological many-body phenomena, and magnetism, among others. The kagome metal CsM3Te5 (where M = Ti, Zr, or Hf) exhibits both superconductivity and nontrivial topological electronic properties, offering a promising platform for exploring topological superconductivity. This study employs first-principles density functional theory calculations to systematically analyze the elastic, mechanical, vibrational, thermodynamic, and electronic properties of CsM3Te5 (M = Ti, Zr, Hf). Our calculations reveal that the studied compounds - CsTi3Te5, CsZr3Te5, and CsHf3Te5 - are ductile metals with elastic properties akin to the hexagonal Bi and Sb, with average elastic constants, including a bulk modulus of 27 GPa, a shear modulus of 11 GPa, and Young's modulus of 29 GPa. We observe peculiar dispersionless, flat, phonon branches in the vibrational spectra of these metals. Additionally, we thoroughly analyze the symmetries of the zone-center phonon eigenvectors and predict vibrational fingerprints of the Raman- and infrared-active phonon modes. The analysis of thermodynamic properties reveals the Einstein temperature for CsTi3Te5, CsZr3Te5, and CsHf3Te5 to be 66, 54, and 53 K, respectively. Our orbital-decomposed electronic structure calculations reveal significant in-plane steric interactions and multiple Dirac band crossings near the Fermi level. We further investigate the role of spin-orbit coupling effect on the studied properties. This theoretical investigation sheds light on the intriguing quantum behaviour of kagome metals. © 2024, CC BY.

关键词： Spin orbit coupling