The deformation and work hardening behaviour of a SPD processed Al-5Cu alloy

Abstract

An Al-5wt.%Cu alloy supersaturated with Cu in solid solution was subjected to equal channel angular pressing (ECAP). The microstructuralevolution was systematically investigated by backscattered electron (BSE)imaging, electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). It isrevealedthata bimodal grain structurecomposed of coarse micron-sized grains and submicron-sized grains was developed after fourpassesof ECAP. Tensile testingshowed that a high ultimate tensile strength of ~500MPa, a high elongation to failure of ~28%anda uniform elongation of ~5% wereachieved simultaneously.The deformation behaviourand the grain structure evolution during ECAP, the strengtheningmechanismsof theas-deformed material, and especially, the roleplayed by a high content of Cu have been discussed.