Formation mechanism for nanodefects on surfaces of loaded metals

Abstract

Tunneling profilometry is used to investigate the shape and orientation of defects that form at the surfaces of Cu, Au, Mo and Pd under loading. The defects have the shape of an indented prism. The value of the angles at the tip of the defects coincide with the angles between glide planes, while the orientation of the walls coincide with the orientation of these planes. At the edges of the defects there exist “swellings” caused by expulsion of material at the surface. Based on these results, the creation of these defects is explained by the exit of dislocations as they burst through barriers formed at intersecting glide planes.