Static recrystallization kinetics and texture evolution of low-temperature extruded Mg-Zn-Ca alloy during annealing
(1. Guangdong Key Laboratory for Advanced Metallic Materials Processing and Forming, National Engineering Research Center of Near-net-shape Forming for Metallic Materials, South China University of Technology, Guangzhou 510640, China;
2. Department of Mechanical, Industrial and Mechatronics Engineering, Toronto Metropolitan University, Toronto, Ontario M5B 2K3, Canada)
2. Department of Mechanical, Industrial and Mechatronics Engineering, Toronto Metropolitan University, Toronto, Ontario M5B 2K3, Canada)
Abstract: A low-alloyed Mg-1.2Zn-0.1Ca alloy was extruded at 150 °C, followed by annealing at varying temperatures of 200-300 °C. The microstructural evolution and static recrystallization kinetics were investigated. The as-extruded alloy exhibited a bimodal structure consisting of fine recrystallized grains of 0.8 μm and coarse un- recrystallized grains, with a recrystallized fraction of ~67%. The recrystallization process at 250 °C was identified to be appropriate with a slow recrystallized grain growth rate. The grains with and orientations exhibited preferential growth advantages during long-term annealing. Grain boundary segregation exerted a strong Zener pinning effect on the grain boundaries, which not only increased the grain growth activation energy, but also affected the texture evolution.
Key words: Mg-Zn-Ca alloy; annealing; texture; grain growth; static recrystallization kinetics