Microstructural evolution during recovery of deformed aluminium—Effect of deformation strain

Abstract

Recovery takes place during annealing of a deformed metal, releasing some of the stored energy. Many recovery mechanisms have been proposed in the literature and these mechanisms strongly depend on the deformation microstructure. In this work, recent progress in the study of recovery in aluminium is reviewed. In lightly deformed aluminium, subgrain growth (through boundary migration and coalescence) is found to be an important recovery mechanism, whereas in heavily deformed samples, uniform coarsening through Y-junction motion is found to be the dominant recovery mechanism. The kinetics of recovery follows a universal coarsening model for aluminium deformed to both low and high strains, in which the apparent activation energy increases in the course of recovery. Furthermore, a new definition of recovery is suggested to be compatible with observations at both low and high strains.