Review
Materials Science, Multidisciplinary
Bo Zhu, Dan Zhao, Yihan Niu, Zhenqiao Zhang, Hongwei Zhao
Summary: Nanotwinned high entropy alloys (HEA) have remarkable mechanical properties, but the influence of twin boundaries (TB) on deformation behavior during friction and nanocutting processes is unclear. Molecular dynamics simulations show that TB inhibits dislocation slip, and lateral atom movement leads to TB migration. Backward scratching generates more sessile dislocations, contributing to strengthening and dislocation hardening.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Engineering, Mechanical
Xiaorong Liu, Dongpeng Hua, Yeran Shi, Zhuobin Huang, Qing Zhou, Shuo Li, Haifeng Wang
Summary: By comparing the dislocation patterning and scratch system dependence between TiZrVTa high entropy alloy (RHEA) and pure Ta under tribological loading, this study reveals that TiZrVTa RHEA exhibits a stable and excellent tribological response due to the pinning effect of lattice distortion and chemical composition fluctuations on dislocations. RHEA shows better tribological properties than pure Ta in any scratch system, and dislocation patterning is more concentrated at the scratching trace. The expansion of dislocation patterning in RHEA when scratching along the slip system ((110)[1-10]) indicates the possibility of severe plastic deformation under favorable stress conditions. This study aims to deepen the understanding of the excellent tribological properties of RHEA and facilitate the development of RHEA with improved tribological performance.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Wan Wang, Dongpeng Hua, Dawei Luo, Qing Zhou, Shuo Li, Junqin Shi, Haifeng Wang
Summary: This study investigates the unique deformation mechanism of CoCrNi medium entropy alloy during nanoscratching using molecular dynamics simulation, emphasizing the characteristics of dislocation reaction and evolution, as well as the impact of defect structures on the performance of MEAs. The study provides insight into the development of new MEAs with excellent tribological performance by analyzing dislocation evolution and deformation mechanisms under tribological loads.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Yeran Shi, Wenting Ye, Dongpeng Hua, Qing Zhou, Zhuobin Huang, Yuxin Liu, Shuo Li, Ting Guo, Yongnan Chen, Stefan J. Eder, Haifeng Wang
Summary: This article reports a groundbreaking study on CoCrFeMnNi/Gr nanocomposites, highlighting their exceptional mechanical properties. The authors use molecular dynamics simulations to reveal the profound impact of graphene on the nucleation and propagation of dislocations in HEAs. They demonstrate that the high stresses at the interface between HEA and graphene lead to out-of-plane deformation of graphene, accommodating the plasticity of HEA. The authors also establish a relationship between the mechanical properties of the nanocomposites and the tensile direction and thickness of HEA. These findings are crucial for the design of advanced materials with unprecedented strength and ductility.
MATERIALS TODAY PHYSICS
(2023)
Article
Chemistry, Physical
Jie Zhang, Wenyue Li, Ruiqiang Qin, Ping Chen, Yanmin Liu, Xiongjun Liu, Lei Gao
Summary: In this study, molecular dynamics simulations were used to investigate the friction and wear mechanisms of CrCoNi medium-entropy alloy with varying Cr content. The results showed that decreasing Cr content led to a decrease in friction coefficient, while increasing hardness and normal force, with resistive force being inversely proportional to the initial Cr content.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Junqiang Ren, Wei Li, Qi Wang, Rui Yang, Qing Gao, Junchen Li, Hongtao Xue, Xuefeng Lu, Fuling Tang
Summary: Molecular dynamics simulations were used to investigate the nanoscale tribology behavior of Ti-based FeCoNiTi High-entropy alloy (HEA) coating through nanoscratching. The results showed that the Ti-based HEA coating with the interface (001)HEA||(0001)Ti had the smallest coefficient of friction (COF) and was the most suitable as the coating interface. The increase in cutting velocity resulted in an increase in frictional force influenced by the disordered atomic structure. The HEA coating effectively protected the pure Ti substrate and prevented dislocation slip and deformation twinning.
Article
Materials Science, Coatings & Films
Shuo Li, Wen-Ting Ye, Ye-Ran Shi, Qing Zhou, Yong-Nan Chen, Ting Guo, Yu-Xin Liu, Lai-Chang Zhang, Hai-Feng Wang
Summary: In this study, we demonstrate that the tribological properties of Fe20Ni20Cr20Co20Cu20/graphene composite coatings can be improved by introducing a graphene layer, addressing the issues of low yield strength and wear in FCC single phase high entropy alloy. Molecular dynamics simulations reveal that the choice of graphene geometry and embedding position significantly affect the friction reduction and anti-wear of the coatings. The graphene interface not only blocks dislocations from the high entropy alloy but also reduces atom accumulation at the surface during sliding. Temperature effects on the tribological behavior of the coatings are also investigated. Experimental nanoscratch tests confirm the simulation results, providing theoretical and technical support for the design of wear-resistant self-lubricating coatings and the application of high entropy alloy coating materials.
SURFACE & COATINGS TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Junwei Miao, Hui Liang, Aijun Zhang, Junyang He, Junhu Meng, Yiping Lu
Summary: The high-entropy alloy EHEA exhibits minimal friction and wear when sliding against SiC at room temperature. However, as the temperature increases, the wear rate gradually increases while the friction coefficient sharply decreases above 600 degrees Celsius.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Materials Science, Coatings & Films
Yucheng Yang, Yaojia Ren, Yanwen Tian, Kaiyang Li, Lichun Bai, Qianli Huang, Quan Shan, Yingtao Tian, Hong Wu
Summary: This study systematically investigated the microstructural evolution and tribological behavior of FeCoCrNiMoSix HEA coatings prepared by laser cladding on Q235 steel substrates. The results showed that increasing Si content can improve the hardness and wear resistance of the coatings.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Liang Zhang, Kun Qian, Jun Huang, Mao Liu, Yasushi Shibuta
Summary: The study utilized molecular dynamics simulation and machine learning methods to investigate the mechanical properties of non-equiatomic high-entropy alloys, establishing a database describing the relationship between material composition and mechanical properties based on experimental testing. The deep neural network (DNN) model outperformed others in binary classification of yield stress, with the elemental composition strategy guiding the design of polycrystal samples. This research demonstrates that computational study combined with machine learning can provide valuable guidance for designing high-strength HEAs and accelerating the development of new alloy materials.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Materials Science, Multidisciplinary
Xianghua Xu, Wengang Fan, Baozhen Li, Jianguo Cao
Summary: The study reveals that the crystal anisotropy of GaAs affects its deformation behavior and residual stress distribution, which are closely related to various parameters during the scratching process. Residual stress is mainly concentrated in the scratching region and distributed symmetrically.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2021)
Article
Chemistry, Physical
Junye Li, Liguang Dong, Xiwei Dong, Weihong Zhao, Jianhe Liu, Jiaxin Xiong, Chengyu Xu
Summary: The wear performance and protection ability of FeNiCrCoCu HEA coating on Cu substrate were studied using molecular dynamics, showing that the friction coefficient of abrasive particle decreased with cutting velocity. The research revealed that HEA coatings can effectively improve wear resistance, especially in areas of high stress concentration below abrasive particles.
APPLIED SURFACE SCIENCE
(2021)
Article
Engineering, Mechanical
Zhaobing Cai, Zheng Wang, Yue Hong, Bingwen Lu, Jin Liu, Yang Li, Jibin Pu
Summary: Plasma nitriding was used to improve the tribological properties of AlCrTiV and AlCrTiVSi high-entropy alloy films, resulting in significantly improved microstructure and tribological properties. The treatment led to increased nano-hardness, reduced wear degree or wear rate, and the plasma-nitrided AlCrTiV HEA film exhibited the lowest friction coefficient and best wear-resistance.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Jie Lu, Guoliang Ren, Ying Chen, Han Zhang, Ling Li, Aihui Huang, Xuanzhen Liu, Huangyue Cai, Xiao Shan, Lirong Luo, Xiancheng Zhang, Xiaofeng Zhao
Summary: This study investigates the effect of elemental sluggish diffusion on the oxidation resistance of high-entropy alloys. By comparing the oxidation behavior and calculating the diffusivities of metal elements in different alloys, it is found that the AlCoCrFeNi HEA exhibits better oxidation resistance due to its lower diffusion rate of Al.
Article
Nanoscience & Nanotechnology
Diana Farkas
Summary: Atomistic simulation studies on deformation behavior in a model quinary high entropy FCC alloy show that local composition fluctuations in random alloys make dislocation glide more difficult, resulting in higher strength and less plastic deformation compared to average atom materials.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)