Anomalous interaction between dislocations and ultra-small voids

TL;DR

This study uses molecular statics simulations to explore how ultra-small voids influence dislocation behavior, revealing complex interactions where applied shear load can increase pinning strength and cause multiple critical resolved shear stress values.

Contribution

It uncovers the non-trivial interaction mechanisms between dislocations and nanovoids, highlighting load-dependent pinning strength and multiple CRSS phenomena.

Findings

Shear load enhances nanovoid pinning strength.

Multiple CRSS values observed for a single nanovoid.

Dislocation-void interactions are more complex at the nanoscale.

Abstract

We carry out the molecular statics simulations of depinning of an edge dislocation at voids of diameters of the order of ~1 nm. We show that the dislocation-void interactions are non-trivial as the applied shear load is found to enhance the pinning strength of the nanovoid itself. This leads to the surprising observation of multiple CRSS values for a given nanovoid.