title: Molecular dynamics simulation of nanoindentation on Cu/Ni nanotwinned multilayer films using a spherical indenter.
abstract: We performed molecular dynamics simulation of nanoindentation on Cu/Ni nanotwinned multilayer films using a spherical indenter, aimed to investigate the effects of hetero-twin interface and twin thickness on hardness. We found that both twinning partial slip (TPS) and partial slip parallel with twin boundary (PSPTB) can reduce hardness and therefore should not be ignored when evaluating mechanical properties at nanoscale. There is a critical range of twin thickness λ (~25 Å < λ < ~31 Å), in which hardness of the multilayer films is maximized. At a smaller λ, TPSs appear due to the reaction between partial dislocations and twin boundary accounts for the softening-dominated mechanism. We also found that the combination of the lowered strengthening due to confined layer slips and the softening due to TPSs and PSPTBs results in lower hardness at a larger λ.
authors: College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.
authors: Tao
authors: T
authors: Fu
authors: College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.|State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China.
authors: Xianghe
authors: X
authors: Peng
authors: Advanced Manufacturing Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
authors: Xiang
authors: X
authors: Chen
authors: College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.
authors: Shayuan
authors: S
authors: Weng
authors: College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.
authors: Ning
authors: N
authors: Hu
authors: College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.
authors: Qibin
authors: Q
authors: Li
authors: College of Aerospace Engineering, Chongqing University, Chongqing 400044, China.|Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
authors: Zhongchang
authors: Z
authors: Wang