Insights into the evolution of texture and mechanical properties during warm rolling and annealing of Mg–2Zn-0.5Ca alloy

Abstract

In this work, we systematically investigated the microstructure, texture evolution and mechanical properties of Mg–2Zn-0.5Ca alloy during warm rolling and annealing. The results showed that the net-like Mg6Zn3Ca2 secondary phases are evolved into short wire-like and fragmented into smaller pieces with the increasing rolling reduction. Besides, some recrystallization grains can be generated with a higher rolling reduction, resulting in a significant grain refinement, which is prone to suppress the activation of twinning. The formation of a double-peak texture with basal poles splitting from the normal direction (ND) towards the transverse direction (TD) can be mainly ascribed to the prismatic <a> slip during warm rolling. The formation of TD-oriented recrystallized grain leads to a transformation from a broadening of angular distribution towards the rolling direction (RD) to a broadening of angular distribution towards the TD. Moreover, the yield strength is dramatically enhanced by the synergetic strengthening effect of grain refinement, work hardening, and texture evolution. After annealing, the sample with high rolling reduction can achieve a combination of high yield strength and high formability due to the fine grains structure containing massive precipitates, which is also featured by an elliptical shape texture with basal poles inclining towards RD and TD.