Nanoscale Metal-Metal Contact Physics from Molecular Dynamics: The Strongest Contact Size

Hojin Kim, Purdue University - Main Campus
Alejandro Strachan, Purdue University - Main Campus

Abstract

Using molecular dynamics we find that the tensile strength of the contacts between two clean platinum surfaces with nanoscale asperities is strongly size dependent with a maximum strength for contact lengths of approximately 5 nm. This is the first time a strongest size is observed in single crystals. The strengthening with decreasing size down to 5 nm results from a decrease in the initial density of mobile dislocations available for plastic deformation and the subsequent weakening originates from a reduction in the constraint to mechanical deformation inside the contact by the bulk.

Discipline(s)

Engineering | Nanoscience and Nanotechnology