title: The rate sensitivity and plastic deformation of nanocrystalline tantalum films at nanoscale.
abstract: Nanoindentation creep and loading rate change tests were employed to examine the rate sensitivity (m) and hardness of nanocrystalline tetragonal Ta films. Experimental results suggested that the m increased with the decrease of feature scale, such as grain size and indent depth. The magnitude of m is much less than the corresponding grain boundary (GB) sliding deformation with m of 0.5. Hardness softening behavior was observed for smaller grain size, which supports the GB sliding mechanism. The rate-controlling deformation was interpreted by the GB-mediated processes involving atomic diffusion and the generation of dislocation at GB.
authors.affiliation: National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, People's Republic of China. mengxk@nju.edu.cn.
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Cao
authors.forename: Qianwei
authors.initials: Q
authors.lastname: She
authors.forename: Yongli
authors.initials: Y
authors.lastname: Huang
authors.forename: Xiangkang
authors.initials: X
authors.lastname: Meng