个人信息Personal Information
性别：男
学科：力学. 航空宇航科学与技术. 材料科学与工程. 机械工程. 冶金工程. 先进制造. 航空工程. 材料工程. 冶金工程. 机械工程. 固体力学
多尺度力学，宏微观力学，梯度结构材料，界面力学，固体本构关系，应变梯度理论，晶体塑性有限元，离散位错动力学，分子动力学，高熵合金，大数据与机器学习，材料基因，极端力学，高性能材料，材料的增强与增韧
2020-05-15 陆晓翀（博士生）的论文“Cyclic plasticity of an interstitial high-entropy alloy: Experiments, crystal plasticity modeling, and simulations”在期刊 Journal of the Mechanics and Physics of Solids 上在线发表。
发布时间：2020-05-15
Highlights
•The Fe49.5Mn30Co10Cr10C0.5 (at.%) interstitial high-entropy alloy (iHEA) exhibited a stress level–dependent ratcheting.
•The martensitic phase transformation is more significant during cyclic deformation than tensile testing.
•Hierarchical structures formed by multiple twins and HCP plates promote the cyclic hardening of the iHEA.
•A developed crystal plasticity model helped analyze the relationship between the microstructures and the ratcheting.
Abstract
The development of high-entropy alloys (HEAs) comprising multiple principal components is an innovative design strategy for metallic materials from the perspective of thermodynamic entropy. However, despite their potential candidacy for engineering applications, the lack of research on the cyclic loading responses as well as constitutive modeling of the HEAs is a major constraint. Therefore, the present work focuses on the cyclic plasticity of a typical carbon-doped interstitial HEA (iHEA) with nominal composition Fe49.5Mn30Co10Cr10C0.5 (at.%). The results of stress-controlled cyclic tests with nonzero mean stress showed that the iHEA exhibits significant cyclic hardening and stress level–dependent ratcheting. Owing to its improved cyclic hardening, the saturated ratcheting strain rate of the iHEA is lower than that of conventional steels such as the 316L stainless steel. Furthermore, microscopic characterizations revealed that the cyclic deformations caused massive martensitic phase transformation and hierarchical structures in the iHEA. The experimental results were used to develop a physical mechanism-based crystal plasticity constitutive model that is capable of describing the cyclic plasticity of the iHEA, which was implemented into a finite element framework. The simulation results showed that the loading stress significantly affected the microstructural evolutions, leading to a stress level–dependent cyclic plasticity. Thus, this investigation provides a fundamental basis for fatigue tests and service life prediction/optimization of the iHEA in the future, which can promote its engineering applications.
Link
https://doi.org/10.1016/j.jmps.2020.103971