文献类型：期刊文献

英文题名：Size-dependent deformation mechanisms in copper gradient nano-grained structure: A molecular dynamics simulation

作者：He, Chen-Yun[1];Yang, Xiao-Feng[1];Chen, Hao[1];Zhang, Yong[1];Yuan, Guang-Jian[1];Jia, Yun-Fei[1];Zhang, Xian-Cheng[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China

年份：2022

卷号：31

外文期刊名：MATERIALS TODAY COMMUNICATIONS

收录：;EI(收录号：20220811702909);WOS:【SCI-EXPANDED(收录号:WOS:000761184100002)】；

基金：The authors would like to acknowledge gratefully for the financial support through NSFC of China (52005186, 51725503, 51575183) and 111 Project. Zhang XC is also grateful for the support by Major Program of National Natural Science Foundation of Shanghai (2019-01-07-00-02-E00068).

语种：英文

外文关键词：Gradient nano-grained structure; Molecular dynamics; Inverse Hall-Petch relationship; Copper

摘要：Gradient nano-grained (GNG) structures exhibit an excellent combination of high strength and toughness. In this paper, molecular dynamics (MD) simulations have been utilized to investigate the tensile properties and related deformation mechanisms of GNG copper structures. Results show that larger gradients give higher strength within a certain size scale range. In the GNG structure, the grain size heterogeneous leads to the non-uniform stress distribution, and the synergistic deformation induced inverse Hall-Petch phenomenon is observed. Furthermore, while both large- and small-grained layers begin to have plastic deformation simultaneously, the dominant deformation mechanism is found to vary with grain size. For grains with 30-100nm, dislocation slips emitted from grain boundaries (GBs) dominate deformation, whereas GB activities, such as GB sliding and/or grain rotation, become the main deformation carrier for grains with 10-20nm. Our results provide a deeper understanding of the deformation mechanisms of GNG copper structures and give guidance for design GNG copper structures.