Size-dependent hardness of nanoscale metallic contacts from molecular dynamics simulations

作者：Kim Hojin^*; Strachan Alejandro

来源：Physical Review B, 2012, 86(6): 064101.

DOI：10.1103/PhysRevB.86.064101

We characterize how size and shape affects the hardness of nanoscale metallic contacts using large-scale molecular dynamics (MD) simulations. High-aspect-ratio contacts continue the experimentally observed trend of hardening with decreasing contact size down to the sub-10-nm regime. However, we find that this effect is shape dependent and the rate of hardening with decreasing contact size diminishes as the aspect ratio of the asperities becomes smaller. Interestingly, low-aspect-ratio asperities that can support simple dislocation glide exhibit softening with decreasing size. A detailed analysis of the MD trajectories reveals the dislocation mechanisms that govern these complex size effects.

• 出版日期2012-8-6