Article
Materials Science, Multidisciplinary
Du Cheng, Kang Wang, Bi-Cheng Zhou
Summary: This study critically reviews the crystal structures and stabilities of phases in the Mg-Zn system and identifies three key unanswered questions. Using first-principles calculations, the atomic structures of GP zones are predicted, the structures of beta(1)' precipitates are provided, and the origin of the two distinct multiple orientations between the beta(2)' phase and the matrix is traced. A feasible precipitation sequence in Mg-Zn alloys is suggested.
Article
Chemistry, Physical
Jacqueline Hidalgo-Jimenez, Jorge M. Cubero-Sesin, Kaveh Edalati, Sakine Khajavi, Jacques Huot
Summary: In this study, the activation problem of Laves phase high-entropy alloys in hydrogenation process was successfully solved using high-pressure torsion. The results showed that the HPT-processed samples were able to rapidly absorb hydrogen at room temperature, indicating that HPT processing is an effective strategy for developing active hydrogen storage materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Yuji Ikeda, Tanja S. Lehmann, Marc Widenmeyer, Mauro Coduri, Blazej Grabowski, Rainer Niewa
Summary: This study revisits the crystal structure and phase stability of Co2N using experiments and first-principles calculations, confirming the stable crystal structure of Co2N as an isotype of eta-Fe2C and Co2C with the space group Pnnm. The research also highlights the importance of considering strong electron correlation in transition metal nitrides for predicting correct experimental structures and magnetic states, with an effective value of U-eff = 2.75 eV identified for Co2N.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Guangzong Xing, Takahiro Ishikawa, Yoshio Miura, Takashi Miyake, Terumasa Tadano
Summary: This study investigates the thermodynamic stability of binary R1-xFex compounds using first-principles calculations based on density functional theory at finite temperature. The findings show that entropy contributions, including electronic and vibrational free energies, are essential for accurately predicting the stability of these alloys. The results indicate that vibrational entropy plays a key role in stabilizing various R1-xFex compounds with increasing temperature, suggesting the possibility of synthesizing these compounds at high temperatures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Metallurgy & Metallurgical Engineering
Yu Zhang, Jing Bai, Ziqi Guan, Xinzeng Liang, Yansong Li, Jianglong Gu, Yudong Zhang, Claude Esling, Xiang Zhao, Liang Zuo
Summary: The Ni2-xMn1+x+ySn1-y system with excess Mn was systematically investigated using first-principles calculations. The results showed that the excess Mn atoms occupied the sublattices of Ni or Sn, and the phase stability of the austenite decreased with an increase in Mn content. The alloys with large magnetic moments of ferrimagnetic austenite underwent martensitic transformation. Valence electrons mainly distributed around Ni or Mn-Ni atoms and bonded with normal Mn atoms. The findings provide a theoretical foundation for further development of the Ni2-xMn1+x+ySn1-y system as potential ferromagnetic shape memory alloys.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2023)
Article
Materials Science, Multidisciplinary
M. Y. Raia, R. Masrour, M. Hamedoun, J. Kharbach, A. Rezzouk, A. Hourmatallah, N. Benzakour, K. Bouslykhane
Summary: In this study, the thermodynamic, band structure, density of states, magnetic, thermoelectric, and optical properties of Co2TiAl, Co2TiGa, and Co2TiIn full Heusler compounds in the L2(1) phase were investigated using the full-potential linearized augmented plane wave (FP-LAPW) method. The results show that the system is more stable in the ferromagnetic state. The elastic constants satisfy the stability criteria, and the calculated magnetic moments confirm the half-metallic behavior of Co2TiAl and Co2TiGa systems.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Chemistry, Physical
Joakim Brorsson, Anders E. C. Palmqvist, Paul Erhart
Summary: The study demonstrates that pseudobinary Ba8AlxGayGe46-x-y clathrates undergo order-disorder transitions with varying temperatures, with Ga-containing systems exhibiting lower transition temperatures than Al-containing systems. Experimental Al and Ga site occupation factors show partial agreement with simulated results, while the challenges in synthesizing Ba8AlxGe46-x and Ba8AlxSi46-x samples near the stoichiometric 16:30 composition ratio are explained.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Materials Science, Multidisciplinary
Pei-Han Sun, Jian-Feng Zhang, Kai Liu, Qiang Han, Zhong-Yi Lu
Summary: The study found that the superconducting pairing in LaO belongs to the BCS type, with the heavy La atoms' electrons and phonons playing a major role in electron-phonon coupling. Biaxial tensile strain and pure electron doping can enhance the superconducting Tc of LaO, and with synergistic effect, Tc can be even higher. Additionally, superconductivity in LaO thin film remains down to the trilayer thickness with a Tc of 1.4 K.
Article
Materials Science, Multidisciplinary
Craig A. J. Fisher, Ayako Taguchi, Takafumi Ogawa, Akihide Kuwabara
Summary: In this study, the structural phase stability and phase transition behavior of LaScO3 perovskite were investigated using density functional theory and the SCAN meta-GGA potential. It was found that LaScO3 transitions from an orthorhombic structure at low temperatures to a cubic structure at high temperatures through intermediate pseudo-tetragonal and tetragonal structures. The large difference in lattice enthalpy between the orthorhombic and cubic structures may explain the difficulty in stabilizing the cubic phase at room temperature.
MATERIALS TODAY COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Xin Wang, Yehui Zhang, Shiji Xu, Xiang Ming Chen, Laurent Bellaiche, Bin Xu
Summary: We report the theoretical design of a multiferroic material Lu1-xGaxFeO3 based on density functional theory calculations. By varying the concentration of Ga, different structural transitions and variations in electronic properties can be achieved, which show potential for various applications.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Diana Denice, A. Arya, Manoj Kumar, Gopika Vinod
Summary: This study investigates the electronic and cohesive properties of six silica polymorphs using Density Functional Theory (DFT), and suggests that adjusting the Hartree-Fock exchange energy fraction can improve the accuracy of the calculations.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Sajib K. Barman, Sarah C. Hernandez, Raymond Atta-Fynn
Summary: By using density functional theory, we systematically studied the changes in the structural and electronic properties of 6-Pu-Ga alloys with increasing Ga concentrations. The results show that the alloy stability increases and the alloying reaction is exothermic as the Ga concentration increases. The electronic interaction between Pu and Ga is primarily governed by the hybridization between Pu 6d and Ga 4p states.
COMPUTATIONAL MATERIALS SCIENCE
(2024)
Article
Physics, Multidisciplinary
Jinyu Li, Chunlei Zhao, Wei Li, Qingying Ren, Jie Xu, Wei Xu
Summary: This study investigates the geometric structure and electronic properties of intrinsic silicene and gallium-doped silicene using first-principles calculations. The adsorption properties of CO, SO2, NH3, and H2O molecules on these materials were analyzed. The results demonstrate that gallium-doped silicene exhibits stronger adsorption capacity compared to intrinsic silicene.
Article
Physics, Multidisciplinary
Yang Shun-Jie, Li Chun-Mei, Zhou Jin-Ping
Summary: Using the exact Muffin-Tin orbital method combined with the coherent potential approximation, the effect of magnetic disordering and alloying effects on the phase stability of L21- and D022-Co2CrZ (Z = Ga, Si, Ge) alloys are systematically investigated at 0 K. It is found that magnetic disordering has a significant impact on the stability of phases, and the addition of Si and Ge can promote the mechanical stability of L21-Co2CrGa alloy.
ACTA PHYSICA SINICA
(2022)
Article
Materials Science, Multidisciplinary
Masaaki Geshi, Hiroki Funashima, Gayan Prasad Hettiarachchi
Summary: This study investigates the high-pressure phases of sulfur using high-precision first-principles calculations. It is found that the proposed simple cubic (sc) structure is not the ground state at any pressure value, and compressed sulfur undergoes a first-order phase transition to a body-centered-cubic phase above 500 GPa. The findings highlight the importance of careful treatments necessary when calculating high-pressure states using the pseudopotential method.
Article
Chemistry, Physical
Hui Yu, Shuo Cao, Sabry S. Youssef, Ying-Jie Ma, Jia-Feng Lei, Yang Qi, Qing-Miao Hu, Rui Yang
Summary: The CRSS and plastic deformation of titanium with HCP structure are highly anisotropic, alloying affects the CRSS, and rational composition design can improve mechanical properties. Prediction of CRSS is challenging due to atomic randomness of the alloy, and first-principles methods are used in this study to calculate GSFEs for Ti-Al alloys and evaluate CRSS within a Peierls-Nabarro model framework. Increasing Al concentration in the alloy impacts the GSFE and CRSS, which successfully explains the measured mechanical properties of the alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Shu-Ming Chen, Ze-Jun Ma, Shi Qiu, Lian-Ji Zhang, Shang-Zhou Zhang, Rui Yang, Qing-Miao Hu
Summary: Phase decomposition significantly affects the mechanical properties of high entropy alloys (HEAs). In this study, we successfully predicted the phase decomposition of the Hf-Nb-Ta-Ti-Zr alloy by combining first-principles methods and thermodynamic models. The predicted results are in good agreement with experiments and simulations, and reveal the influence of phase decomposition on the strength of the alloy.
Article
Chemistry, Physical
Yue Guan, Xiaodan Li, Qingmiao Hu, Dandan Zhao, Lin Zhang
Summary: In this paper, the thermal, mechanical, electronic and optical properties of hetemstructures composed of boron arsenide (BAs) and WX2 (X = S, Se) were systematically investigated using first principle calculations. It was found that the heterostructures are structurally, dynamically, and mechanically stable. The investigated van der Waals (vdWs) heterostructures (BAs/WS2 and BAs/WSe2) are all direct bandgap semiconductors and exhibit high carrier mobility and optical absorptivity, making them highly efficient for solar energy. The properties of BAs/WX2 hetemstructures are significantly affected by spin-orbit coupling and external electric field.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Min Huang, Zhiqiang Qiu, Fang Wang, Hubin Luo, Jian Zhang
Summary: The effect of multicomponent film diffusion on the microstructure and magnetic properties of sintered Nd-Fe-B magnets was investigated. The results showed that multicomponent diffusion magnets exhibited higher coercivity and magnetic energy product compared to Tb diffusion magnets. The optimized distribution of Tb and the presence of grain boundary phases were identified as key factors for the significant enhancement of coercivity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Physics, Condensed Matter
Shuo Cao, Yang Li, Lian-Ji Zhang, Yan-Ting Yang, Jian-Rong Liu, Rui Yang, Qing-Miao Hu
Summary: Precipitation strengthening of silicides is important for improving the creep resistance of high-temperature titanium alloys. However, the oversize and concentrated silicides reduce the ductility of the alloys. It has been found that Zr and Hf stabilize Ti5Si3, promoting the nucleation and refinement of silicide particles, while beta stabilizers and simple metals destabilize Ti5Si3 and suppress its precipitation.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Zhen Zhao, Haoyang Zhao, Hubin Luo, Lei Liu, Yong Ding, Xiangyu Zhang, Xiaohong Yao, Jian Zhang
Summary: Research has shown that the Sm2Co17 phase can undergo plastic deformation through the formation of amorphous shear bands, not just the SmCo5 phase. The interfacial stress significantly affects the formation of amorphous shear bands, and two-phase composites also deform under tensile loading.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
J. X. Yan, Z. J. Zhang, P. Zhang, J. H. Liu, H. Yu, Q. M. Hu, J. B. Yang, Z. F. Zhang
Summary: The development of multi-principal element alloys (MPEAs), also known as high- or medium-entropy alloys (HEAs/MEAs), offers great possibilities for materials innovation. However, designing MPEAs with desired mechanical properties is challenging due to their vast composition space. This study provides an essential criterion to efficiently screen CoCrNi MEAs with outstanding strength-ductility combinations, combining the negative Gibbs free energy difference between face-centered cubic (FCC) and body-centered cubic (BCC) phases, enhancement of shear modulus, and decline of stacking fault energy.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Xue-Chun Zhang, Shuo Cao, Lian-Ji Zhang, Rui Yang, Qing-Miao Hu
Summary: In this paper, the competition between the {110}(111), {112}(111), and {123}(111) slip systems in BCC metals is determined by calculating the unstable stacking fault energy (yus) and Peierls stress (up) of these systems. It is found that yus is proportional to oB thorn G thorn =a2=3, where B, G, and a are the bulk modulus, shear modulus, and lattice constant, respectively. The calculations predict that the {110}(111) slip is prioritized, and up indicates a decrease in dislocation mobility in the order of {110}(111), {112}(111), {123}(111) for most metals. Notably, yus and up are not monotonically related.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Mingpeng Kou, Shuai Cao, Tengfei Wu, Yuheng Xie, Zhi Jia, Hubin Luo, Xiaodong Fan, Guangfei Ding, Bo Zheng, Renjie Chen, Shuai Guo, Aru Yan
Summary: Commercial N55 sintered Nd-Fe-B magnets were significantly improved in coercivity by grain boundary diffusion (GBD) with Tb-Cu and Tb-Y-La-Cu alloys. The increase in coercivity remained large when the proportion of Y was increased and Tb was reduced, accompanied by an optimization of thermal stability. Microstructure analysis showed that the improved performance of the Tb-Y-La-Cu GBD-treated magnet was mainly due to the synergistic effect of Y and La on Tb.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Xue-Chun Zhang, Shuo Cao, Rui Yang, Qing-Miao Hu
Summary: The Peierls stress of FCC structures calculated using the PN model is highly sensitive to various input parameters, such as shear modulus, Poisson's ratio, and generalized stacking fault energy. This sensitivity leads to significant oscillations in the predicted Peierls stress. In this study, we propose a modified model that alleviates the sensitivity of the Peierls stress on the input parameters, resulting in better agreement with experimental values.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Niuniu Wang, Hubin Luo, Lei Liu, Yong Ding, Renjie Chen, Xiangyu Zhang, Xiaohong Yao, Izabela Szlufarska, Aru Yan
Summary: Recently, it has been discovered that SmCo5 can form amorphous shear bands, leading to dislocation-free plastic deformation at large strains. The formation of shear bands is energetically favorable and does not induce high local stress compared to cracking. However, the atomic-level mechanism of the crystalline-to-amorphous transition during shear-band formation remains unclear. This paper investigates the shear deformation of SmCo5 through molecular dynamics simulations and explores the atomic packing in the interfacial zone between the crystal matrix and shear band to understand the behavior of shear-band formation.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Mengmeng Yang, Jiaying Zhou, Haijun Huang, Shuo Cao, Qing-Miao Hu, Wei Li, Qingjun Chen, Yanxin Qiao, Hao Wang
Summary: By using high-throughput first-principles calculations, the segregation capacity of fifteen widely used metallic alloying elements at the grain boundary in low alloy ferritic steel was systematically investigated. The impact of strain energy minimization on segregation was found to be comparable to that of chemical energy minimization, especially for large alloying atoms. The findings suggest that the segregation of large alloy atoms on the grain boundaries can be predicted by their atomic volume, providing valuable insights for alloy development and grain boundary engineering.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Shu-Ming Chen, Yang Gao, Zi-Han Yu, Bi-Ning Liang, Shuo Cao, Rui Yang, Qing-Miao Hu
Summary: According to classical metal physics theory, the substitutional solute atom in dilute metal solid solution occupies the high-symmetry lattice site without destroying the point group symmetry of the host lattice. However, recent first-principles calculations revealed that the substitutional solute atom Mo occupies a low-symmetry off-center position in dilute Ti solid solutions, which breaks the point group symmetry of the hexagonal-close-packed host lattice due to the Jahn-Teller splitting of the degenerated d orbitals of Mo. In this study, we investigated the site occupation of substitutional atom X in dilute Ti-X solid solution with X ranging from V to Zn, and found that Cr, Mn, Fe, and Co exhibit spontaneous symmetry breaking by occupying the low-symmetry off-center site, while V, Ni, Cu, and Zn tend to stay at the high-symmetry lattice site, and this off-center occupation is robust against the size of the supercell and the thermal volume expansion in first-principles calculations.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jialong Tian, Gang Zhou, Wei Wang, Qingmiao Hu, Zhouhua Jiang, Ke Yang
Summary: The effect of cobalt on the precipitation hardening behavior of maraging stainless steels was investigated. It was found that cobalt addition could increase peak hardness and accelerate the aging process, as well as enhance the density of precipitates, leading to a stronger contribution to precipitation hardening.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Haoran Sun, Zhigang Ding, Hao Sun, Junjun Zhou, Ji-Chang Ren, Qingmiao Hu, Wei Liu
Summary: The HCSA scheme efficiently and accurately predicts the SFEs of MPEAs by averaging SFEs from small supercells, outperforming traditional DFT calculations. It has been successfully applied to NiFe and Ni 10 Co 60 Cr 25 W 5 alloys, achieving significant error reduction and holding the potential to accelerate materials design and discovery processes.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2024)