Plastic Deformation Modes of CuZr/ Cu Multilayers

Authors

Yan Cui, Xi’an Jiaotong University
Oscar Torrents Abad, INM-Leibniz Institute for New Materials
Fei Wang, Xi’an Jiaotong University, Xi’anFollow
Ping Huang, Xi’an Jiaotong UniversityFollow
Tian-Jian Lu, Xi’an Jiaotong University, Xi’an
Ke-Wei Xu, Xi’an Jiaotong University
Jian Wang, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2016

Citation

Scientific Reports | 6:23306 | DOI: 10.1038/srep23306

Comments

This work is licensed under a Creative Commons Attribution 4.0 International License

Abstract

We synthesized CuZr/Cu multilayers and performed nanoindentation testing to explore the dependence of plastic deformation modes on the thickness of CuZr layers. The Cu layers were 18 nm thick and the CuZr layers varied in thickness from 4 nm to 100 nm. We observed continuous plastic co-deformation in the 4 nm and 10 nm CuZr − 18 nm Cu multilayers and plastic-induced shear instability in thick CuZr layers (>20 nm). The plastic co-deformation is ascribed to the nucleation and interaction of shear transformation zones in CuZr layers at the adjacent interfaces, while the shear instability is associated with the nucleation and propagation of shear bands in CuZr layers. Shear bands are initialized in the CuZr layers due to the accumulated glide dislocations along CuZr-Cu interfaces, and propagate into adjacent Cu layers via slips on {111} plane non-parallel to the interface. Due to crystallographic constraint of the Cu layers, shear bands are approximately parallel to {111} plane in the Cu layer.