Strengthening mechanisms in a Zr-modified 5083 alloy deformed to high strains

Abstract

The effect of extensive grain refinement through equal-channel angular processing (ECAP) at 300°C on the mechanical properties was examined in a Zr-modified 5083 aluminum alloy. It was shown that any increase in the yield stress (YS) by increasing the number of pressings was attributed to additional contributions from three strengthening mechanisms :(i) grain boundary strengthening related to the size of the crystallites bounded by deformation-induced high-angle boundaries (HAB), (ii) dislocation strengthening related to highly increased dislocation density and(iii)solute strengthening related to promoting dynamic strain aging (DSA) by intense plastic straining