Microstructure evolution and mechanical property of Mg-3Al alloys with addition of Ca and Gd during rolling and annealing process

The formability of magnesium alloys at ambient temperature can be enhanced by alloying additions such as Ca and RE elements, which is ascribed to the weakened basal texture. To produce magnesium alloy sheets with excellent comprehensive performance, the evolution of texture characterization during fabrication process and subsequent effect of texture on mechanical properties are vital controlling factors. In this investigation, three experimental Mg-3Al series alloys were hot rolled and annealed to sheets with 1 mm thickness. The microstructure evolution during rolling and annealing process was investigated. Furthermore, the influence of texture on tensile properties along different tensile directions was also studied. The results show that weakened basal texture and refined grains were achieved with the co-addition of Ca and RE element. However, strengthening of mechanical properties wasn't obtained. During hot rolling process, microstructure was refined, second phase particles broken, and basal texture was increased. While basal texture was weakened during annealing process. Recrystallization behavior influenced by formation of second phase was dominated to attenuate basal texture. Tensile deformation behavior was controlled by basal slip and followed Schmid factor criterion. Moreover, the weakened basal texture and activation of non-basal slips during hot rolling process can contribute to diminish the anisotropy of tensile properties. (c) 2020 Published by Elsevier B.V. on behalf of Chongqing University.