title: Plastic Deformation Modes of CuZr/Cu Multilayers.
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.
authors.affiliation: Statekey Laboratory for Mechanical Behavior of Material, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cui
authors.affiliation: INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbruecken, Germany.
authors.forename: Oscar Torrents
authors.initials: OT
authors.lastname: Abad
authors.affiliation: State Key Laboratory for Mechanical Structure Strength and Vibration, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.affiliation: Statekey Laboratory for Mechanical Behavior of Material, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Huang
authors.affiliation: State Key Laboratory for Mechanical Structure Strength and Vibration, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
authors.forename: Tian-Jian
authors.initials: TJ
authors.lastname: Lu
authors.affiliation: Statekey Laboratory for Mechanical Behavior of Material, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
authors.forename: Ke-Wei
authors.initials: KW
authors.lastname: Xu
authors.affiliation: Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588 USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang