Article
Nanoscience & Nanotechnology
Zachary T. Kloenne, Jean-Philippe Couzinie, Milan Heczko, Roman Groger, Gopal B. Viswanathan, William A. T. Clark, Hamish L. Fraser
Summary: A refined microstructure consisting of bcc precipitates embedded in an ordered B2 matrix has been observed in the refractory high entropy alloy AlMo0.5NbTa0.5TiZr, resembling an inverted superalloy-like micro-structure. Coarsening of the microstructure occurs after aging, resulting in a faceted interface. Misfit dislocations at the interface were observed on the {110} interface plane, extending into the bcc phase, and no lattice invariant deformation normal to the primary {110} planes was observed, indicating a pure expansion transformation between the B2 and bcc phases.
SCRIPTA MATERIALIA
(2023)
Article
Materials Science, Multidisciplinary
X. J. Fan, R. T. Qu, Z. F. Zhang
Summary: The BCC HfNbTaTiZr refractory HEA exhibits remarkable fracture toughness in addition to its high strength, good tensile ductility, and excellent high-temperature properties. This material shows promise for applications in high-temperature structural materials such as in the aerospace field.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Lu Wang, Jiarui Wang, Hongwei Niu, Gongji Yang, Lin Yang, Mingqin Xu, Jiaojiao Yi
Summary: A near-eutectic high-entropy alloy with a soft-hard dual-phase structure was developed by adjusting the composition ratio and annealing process. The alloy exhibited high yield strength and moderate plasticity, but the homogenization process resulted in the formation of micro-pores, leading to a decrease in mechanical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Jiaojiao Yi, Lin Yang, Lu Wang, Mingqin Xu
Summary: A lightweight, refractory high entropy alloy CrNbTa0.25TiZr was prepared by arc-melting under vacuum, with as-cast and annealed samples showing improvement in yield strength and lower density compared to a reference alloy. The evolution of the microstructure highlights the promising strength of CrNbTa0.25TiZr.
METALS AND MATERIALS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Xiaorong Liu, Dongpeng Hua, Wan Wang, Qing Zhou, Shuo Li, Junqin Shi, Yixuan He, Haifeng Wang
Summary: This study investigated the initial dislocation nucleation and motion mechanisms in TaTiZrV high-entropy alloys (RHEAs) and their dependence on temperature through molecular dynamics simulations. The short-range orders in the RHEA facilitate preferential inhomogeneous nucleation at low stress, while compositional fluctuation affects the slipping and moving rate of dislocations. Moreover, the difficulty of initial dislocation nucleation increases with temperature.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Jean-Philippe Couzinie, Milan Heczko, Veronika Mazanova, Oleg N. Senkov, Maryam Ghazisaeidi, Rajarshi Banerjee, Michael J. Mills
Summary: This study analyzes the deformation mechanisms in a two-phase refractory complex concentrated alloy (RCCA) Al0.5NbTa0.8Ti1.5V0.2Zr at 600 degrees C. The alloy exhibits dynamic coarsening of B2 precipitates during mechanical testing and highly localized deformation in wavy bands after a true plastic strain of 0.030. Scanning transmission electron microscopy reveals the presence of paired a/2 <111> dislocations that shear the B2 precipitates cooperatively. Chemical segregation effect is also observed along narrow dislocation bands, possibly to reduce the antiphase boundary energy of the system.
Article
Nuclear Science & Technology
Yun Zong, Naoyuki Hashimoto, Hiroshi Oka
Summary: We developed new body-centered cubic refractory high-entropy alloys with high-irradiation resistance suitable for fusion reactor components. The microstructure and mechanical properties of these alloys were investigated, showing stable behavior at elevated temperatures and increased resistance to irradiation compared to pure tungsten.
NUCLEAR MATERIALS AND ENERGY
(2022)
Article
Nanoscience & Nanotechnology
Hao Qi, Qingyao Lv, Guanglong Li, Yingdong Qu, Ruiming Su, Keqiang Qiu, Wei Zhang, Bo Yu
Summary: Cryogenic treatment at 77K is applied to improve the strength and plasticity balance of BCC type Al1.4CrFe2Ni2 high entropy alloy. The results show that cryogenic treatment has a significant effect on nanophases, dislocations, and mechanical properties. The nanophase size is reduced by 42.7% and the number is increased by 60% after 24 hours of cryogenic treatment. The dislocation morphology evolves and the dislocation density increases significantly. The cryogenically treated Al1.4CrFe2Ni2 HEA exhibits improved mechanical properties, including higher hardness and fracture strength, while maintaining a high fracture strain of up to 40.8%.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
Wenqing Yang, Jiasi Luo, Hui Fu, Chi Fai Cheung, Haihui Ruan, Xu-Sheng Yang
Summary: In this paper, cold rolling and different annealing temperatures were applied to the as-cast TiZrHfTa0.5 alloy. The study found that the most bcc -> hcp phase transition occurred in the cold-rolled plus 870 degrees C-annealed specimens. Atomic-scale observations revealed that this phase transition was further activated in the self-organized gradient worn subsurface, where a dual-phase structure with increased hcp phase fraction accommodated the sliding-caused plasticity.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Wei Zhang, Zhichao Ma, Chaofan Li, Chaowei Guo, Dongni Liu, Hongwei Zhao, Luquan Ren
Summary: A systematic investigation was conducted to study the interphase strengthening effects on the mechanical performances of multiphase high-entropy alloys (HEAs) at micro/nano-scale compared with single phase HEAs. The study revealed that the interphase exhibited significantly higher strength compared to other phases, and the mechanical size effects were independent of the phase type.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Advika Chesetti, Sucharita Banerjee, Sriswaroop Dasari, Mohan Sai Kiran Nartu, S. M. Varahabhatla, Abhishek Sharma, Abhishek Ramakrishnan, Daniel Satko, Stephane Gorsse, Ayman Salem, Rajarshi Banerjee
Summary: A low-density precipitation strengthened CCA, Al10Nb15Ta5Ti30Zr40, with excellent room temperature mechanical properties and high plasticity, has been successfully developed through 3D printing.
SCRIPTA MATERIALIA
(2023)
Article
Physics, Applied
Liang Wang, Xudong Liu, Chunxi Li, Minzheng Yang, Benpeng Wang, Kaisheng Ming, Shijian Zheng, Jun Liang, Yunfei Xue
Summary: Designing a new type of metastable refractory high entropy alloy with transformation induced plasticity effectively addressed the issue of low ductility. The alloy exhibited remarkable ductility and demonstrated good deformability during tension deformation. Through analyzing the variation of lattice distortion, it was believed that the FCC martensite was generated by relaxing the lattice distortion.
APPLIED PHYSICS LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Zhenhua Han, Lingkun Meng, Jun Yang, Gang Liu, Jungang Yang, Ran Wei, Guojun Zhang
Summary: The refractory V-Nb-Ta alloys with single BCC structure exhibited excellent combination of strength and plasticity, which was attributed to the solid solution strengthening effect caused by the large atomic size misfit among Nb, Ta and V elements.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Multidisciplinary
Nikita Yurchenko, Evgeniya Panina, Sergey Zherebtsov, Nikita Stepanov
Summary: The oxidation behavior of refractory (HfCo)(100-x)(NbMo)(x) (x = 0; 10; 25; 40; 75; 100 at.%) high-entropy alloys with a bcc+B2 structure subjected to cyclic oxidation at 1000 degrees C was studied. The addition of (NbMo)(x) deteriorated the spallation resistance and led to complete disintegration. Among the (NbMo)-containing alloys, the (HfCo)(90)(NbMo)(10) alloy with the dual phase bcc+B2 structure showed the most promising oxidation resistance.
APPLIED SCIENCES-BASEL
(2023)
Article
Materials Science, Multidisciplinary
N. Yurchenko, E. Panina, A. Belyakov, G. Salishchev, S. Zherebtsov, N. Stepanov
Summary: High-entropy intermetallics show great potential for high-temperature applications, but there is limited information on their plastic flow behavior and deformation mechanisms. A yield strength anomaly was observed in a refractory AlNbTiVZr0.25 high-entropy alloy during compression tests, possibly connected to the glide of dissociated a (111) superdislocations.
Article
Engineering, Mechanical
Yang Chen, Shuo Wang, Hui Feng, Weipeng Li, Bin Liu, Jia Li, Yong Liu, Peter K. Liaw, Qihong Fang
Summary: By conducting high-resolution transmission electron microscopy and random field theory informed discrete dislocation dynamics simulations, this study reveals the influence mechanism of heterogeneous lattice strain on the complex interaction between dislocations and dislocation loops in high entropy alloys (HEAs) under irradiation. The results show that lattice-strain-induced irradiation hardening decreases, in line with the excellent irradiation hardening resistance of HEAs observed in recent experiments. A new cross-slip mechanism is also discovered, involving the co-linear reaction between dislocations and rhombus perfect loops. This study provides insights into the mesoscopic-level irradiation damage behavior, guiding the development of advanced HEA materials for nuclear energy applications through the regulation of heterogeneous lattice strain.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Engineering, Mechanical
Mingyu Fan, Zhongwu Zhang, Ye Cui, Liyuan Liu, Yingwei Liu, PeterK. Liaw
Summary: A novel nanoscale superlattice precipitate (NSP) with superior strengthening effect is developed by rare-earth Er alloying to magnesium alloys. The newly-developed cast Mg-Y-Zn-Er alloy shows high yield strength, tensile strength, and good ductility. The structure and optimization mechanism of the NSP are systematically investigated using transmission electron microscopy and first-principles calculations.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Correction
Multidisciplinary Sciences
Zongrui Pei, Junqi Yin, Peter. K. K. Liaw, Dierk Raabe
NATURE COMMUNICATIONS
(2023)
Review
Materials Science, Multidisciplinary
Kaixuan Cui, Yong Zhang
Summary: This paper discusses the preparation process, microstructure, hardness, wear resistance, and corrosion resistance of high-entropy alloy films, and analyzes the influence of factors such as nitridation, sputtering power, substrate temperature, and substrate bias on the phase structure of alloy films. High-entropy alloy films can be prepared using various processes. They tend to form a solid solution and amorphous state, and their hardness is much higher than that of traditional films. Some high-entropy alloy films have better corrosion resistance than stainless steel due to the corrosion-resistant elements and amorphous structure. High-entropy alloy films have promising development prospects in wear-resistant coatings, corrosion protection, diffusion barriers, and photothermal conversion coatings.
Article
Chemistry, Physical
Christopher Tandoc, Yong-Jie Hu, Liang Qi, Peter K. Liaw
Summary: Severe lattice distortion is a key feature of high-entropy alloys, but accurate characterizations of lattice distortion are scarce due to high costs. We present a physics-based statistical model for efficient prediction of lattice distortion in refractory non-dilute/high-entropy alloys. The model improves accuracy by considering interatomic bonding properties instead of atomic size mismatch.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
B. Steingrimsson, X. Fan, R. Feng, P. K. Liaw
Summary: Machine learning has become a powerful tool for accurately predicting temperature-dependent yield strengths (YS) of structural materials, especially for multi-principal-element systems. The researchers have developed a bilinear log model that incorporates a break temperature, Tbreak, for predicting temperature-dependent YS of medium-entropy or high-entropy alloys (MEAs or HEAs). This model can guide the design of MEAs or HEAs with attractive high-temperature properties.
APPLIED MATERIALS TODAY
(2023)
Article
Physics, Applied
Rong Hao, Guanhao Liu, Zhong Wang, Huijun Yang, Peter K. Liaw, Junwei Qiao
Summary: This study successfully establishes a model for alloys with low stacking fault energies and predicts their failure threshold. It provides a new approach to further understand the serration mechanism and predict the failure threshold of multicomponent alloys.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Kuan Gao, Yuexin Chu, Weihua Zhou, Yong Tian, Yong Zhang, Yi Li
Summary: This study systematically investigates the phase inversion phenomenon in a high-Al-content B2 refractory high-entropy alloy (RHEA) through thermo-mechanical treatment. The grains of the single B2 phase transform inversely to the BCC+B2 microstructure with a dispersion of spherical B2 precipitates in the BCC grains. The phase inversion process enhances the tensile ductility of the RHEA while maintaining its high specific strength.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Yangyong Zhao, Yuanyuan Bai, Tie Li, Yong Zhang, Eiichi Sato
Summary: Cu-Sn shape-memory microwires were fabricated by a glass-coated melt spinning method. The effects of Sn content on the microstructure and mechanical properties of microwires were investigated. It was found that a high cooling rate in the method greatly improved the mechanical properties and superelasticity of the microwires.
Article
Multidisciplinary Sciences
Shuai Chen, Ping Liu, Qingxiang Pei, Zhi Gen Yu, Zachary H. Aitken, Wanghui Li, Zhaoxuan Wu, Rajarshi Banerjee, David J. Srolovitz, Peter K. Liaw, Yong-Wei Zhang
Summary: This study constructs nanolamellar high-entropy alloys and explores their mechanical properties using molecular dynamic simulation and density functional theory calculation. The results show that the nanolamellar structure exhibits ideal plastic behavior and remarkable shape memory effect, highlighting the importance of nanolamellar structures in controlling the mechanical and functional properties of high-entropy alloys.
Article
Chemistry, Physical
Qingwei Guo, Hua Hou, Kaile Wang, Muxi Li, Peter K. Liaw, Yuhong Zhao
Summary: This study proposes a multiparticle model based on molecular dynamics to investigate the coalescence kinetics during the hot-pressed sintering of a polycrystalline high-entropy alloy. The model accurately captures the accelerated occurrences of various phenomena and validates its feasibility by calculating the Young's modulus, which closely matches the experimental value.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ruixuan Li, Guihong Geng, Yong Zhang
Summary: High-entropy alloys (HEAs) have gained significant attention for their unique composition design and excellent properties, and the concept of entropy regulation has been widely used to develop performance-oriented alloys. Lightweight high-entropy alloys (LHEAs) are important lightweight materials that exhibit special properties due to high alloying elements and high mixing entropy, including high specific strength, high specific hardness, and excellent corrosion resistance. However, there are still unresolved questions regarding phase formation rules and comprehensive performance in specific service environments. This paper reviews the composition design, phase formation rules, mechanical properties, physical properties, and chemical properties of typical LHEAs, highlighting the challenges and future development directions.
MRS COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Fusheng Tan, Li Li, Jia Li, Bin Liu, Peter K. Liaw, Qihong Fang
Summary: The harsh environment of nuclear reactors and flaws in existing materials have created a demand for new alloys. High-entropy alloys (HEAs) have gained attention for their potential in nuclear fields. Multiscale modelling has been used to study the irradiated properties of HEAs, deepening understanding and accelerating the development of irradiation-resistant HEAs. This review introduces the state-of-the-art multiscale modelling used for studying the irradiated properties of HEAs and summarizes representative irradiation-induced microstructures, properties, and damage. By strengthening the application of multiscale modelling, the rational design of high irradiation-resistant HEAs is expected.
ADVANCED POWDER MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Dan Liu, Xi Jin, Huijun Yang, Junwei Qiao, Yong Zhang
Summary: The temperature sensitivity of cobalt-free high-entropy alloys Fe45Mn15Cr15Ni25 and Fe35Mn15Cr15Ni25Al10 was investigated. The addition of aluminum improves the mechanical properties and thermal stability of the alloys, but exacerbates the serration behavior.
Article
Materials Science, Multidisciplinary
Ruixuan Li, Baixue Bian, Gerhard Wilde, Yong Zhang, Sergiy V. Divinski
Summary: The tracer self-diffusion of Co in a compositionally complex AlCoCrFeNiTi0.2 alloy was measured using the radiotracer technique. The analysis of the complex multi-phase microstructure allowed for the determination of volume diffusion coefficients and grain boundary diffusion coefficients.
