Interaction of a mobile {1 1 2} grain boundary with radiation induced defects in a-Fe: Transformation of defects and impact on the shear-coupled grain boundary migration

Abstract

Mobile grain boundaries (GB) may have specific interactions with radiation-induced defects compared with static GBs. In this paper, we consider the GB-defect interactions for the {1 1 2} GB that performs shear coupled grain boundary migration mediated by its glissile disconnections. The conservative motion of this GB facilitates the interaction with radiation-induced defects both, mobile and sessile. While mobile defects interact by diffusing to GBs, sessile defects are approached by moving GBs. Clusters at the GB may either be dragged by disconnections or transformed by the motion of the GB that relocates them into the adjacent grain. In turn, the interaction with point defects and their clusters increases the resolved shear stress necessary for the motion of disconnections and subsequent GB migration. The results obtained are directly applicable to the interaction of radiation induced defects with {1 1 2} deformation twins.