The role of deformation banding in grain refinement under ECAP

Abstract

The mechanism of grain refinement in an Al-5.4Mg-0.4Mn-0.2Sc-0.09Zr alloy subjected to equal-channel angular pressing (ECAP) at 300°C through route BC is considered. It was shown that the formation of geometrically necessary boundaries (GNB) aligned with a {111} plane at e≤1 initiates the occurrence of continuous dynamic recrystallization (CDRX). Upon further strain the GNBs transform to low-to-moderate angle planar boundaries that produces lamellar structure