个人信息Personal Information
学历：博士研究生毕业
学位：工学博士学位
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
2021-04-01 硕士生双思垚论文“Effects of high entropy and twin boundary on the nanoindentation of CoCrNiFeMn high-entropy alloy: A molecular dynamics study”被Computational Materials Science接受发表，被选为"Editor's Choice"
发布时间：2021-04-01
Highlights
•MD is used to study nanoindentation on CoCrNiFeMn high-entropy alloy (HEA).
•There are no obvious load-drop phenomena in the nanoindentation of the HEA.
•The twin boundary provides a slip path for dislocations.
Abstract
To study the effects of twin boundary and high-entropy on elastic–plastic behavior of high-entropy alloys (HEAs), molecular dynamics (MD) was employed to simulate the nanoindentation on single-crystal CoCrNiFeMn HEA (sc-HEA), twinned CoCrNiFeMn HEA (tw-HEA) bicrystal and twinned Ni (tw-Ni) bicrystal. The deformation behaviors of the three samples were then compared with each other. Simulations revealed that the load-drop phenomenon during the indentation in the HEAs is not so apparent as that in the Ni. Microstructure characterization showed that a dense dislocation network was localized below the indentation pit of the HEAs. These phenomena are related to the damping spreading behavior of dislocations underneath the indenter. Through the analysis of the plastic zone underneath the indentation, it is found that the twin boundary inhibits dislocation penetration, and moreover, provides a slipping path for dislocations. The radial distribution of dislocation density proves that dislocations in the indentation of the HEAs are more concentrated than that in the traditional metals. Understanding the sluggish dislocation behavior and twin boundary effect help understand the deformation mechanisms underlying the mechanical response of HEAs.
Link
https://doi.org/10.1016/j.commatsci.2021.110495