Static recrystallization kinetics of a heavily cold drawn AZ31 magnesium alloy under annealing treatment

AZ31 Mg alloy extrusion wires were successfully cold drawn to a cumulative area reduction of 61% at room temperature and then subjected to various annealing treatments. Microstructure, texture evolution, tensile properties and microhardness of the as-deformed and as-annealed samples were investigated. The results showed that grain size was refined after static recrystallization in the severely deformed sample, and the annealing temperature had more significant effect on the microstructural evolution than the annealing time. During the annealing process, the basal texture was notably strengthened and the deformed fibrous texture was evolved gradually from direction to direction. The analysis on the recrystallization kinetic during annealing indicated that it could be well described by JMAK model. The activation energy for recrystallization was calculated to be about 85.9kJ/mol. Moreover, a self-consistent model of static recrystallization occurred during annealing of the heavily deformed AZ31 alloy was proposed. ► PA cold drawn reduction of 61% of an AZ31 Mg alloy was obtained. ► The cracked twins played a role in the work hardening and static recrystallization. ► Texture changes from {0002} direction to to {0002} confirmed the preferential nucleation in twins. ► The recrystallization kinetic was well described by JMAK model. ► The activation energy for recrystallization was calculated to be 85.9 kJ/mol.