Atomic scale modeling of interstitial loop-induced strengthening in nickel

Abstract

Atomic-scale simulations are performed to investigate the interaction between prismatic interstitial loops and moving dislocations in nickel. Depending on their relative position, a loop either drags a dislocation elastically or decorates a dislocation with jogs, resulting in a systematic change of the critical stress for subsequent dislocation glide. Loop-decoration significantly reduces the mobility of a dislocation, and the critical shear stress can increase up to ten times larger than the conventional Peierls stress. This work presents the atomic-scale details of loop-dislocation interaction, thus providing reliable information for parameterizing debris-dislocation interaction in meso- or macro-scale simulations.