A Comparison of the Effects of Pre-ECAR and Post-ECAR Aging on Microstructure and Strengthening in 7050 Al Alloy Sheet

Abstract

Effects of the post-ECAR aging treatment on the microstructural evolution and strengthening were compared with those of the pre-ECAR aging for a wrought 7050 Al alloy sheet that was subjected to severe plastic deformation (SPD) through multiple equal channel angular rolling (ECAR). The post-ECAR aging treatment led to the formation of a nanocrystalline structure with a grain size of ∼100 nm through the precipitation of fine MgZn₂ particles during post-ECAR aging, which pinned the grain boundary motion, and more effectively strengthened the 7050 Al alloy than the pre-ECAR aging.