Pinning interaction between a screw dislocation and a void in fcc copper is investigated by means of molecular dynamics simulation. A screw dislocation bows out to undergo depinning on the original glide plane at low temperatures, where the behavior of the depinning stress is consistent with that obtained by a continuum model. If the temperature is higher than 300 K, the motion of a screw dislocation is no longer restricted to a single glide plane due to cross slip on the void surface. Several depinning mechanisms that involve multiple glide planes are found. In particular, a depinning mechanism that produces an intrinsic prismatic loop is found. We show that these complex depinning mechanisms significantly increase the depinning stress.
@article{arxiv.0710.5811,
title = {Void-induced cross slip of screw dislocations in fcc copper},
author = {Takahiro Hatano and Tetsuya Kaneko and Yousuke Abe and Hideki Matsui},
journal= {arXiv preprint arXiv:0710.5811},
year = {2008}
}