The recrystallization mechanism and its effects on texture in pre-twinned AZ31 magnesium alloy during medium-high temperature impact loading
Xiao Liu, Xiao Feng Zhang, Biwu Zhu, Chao Xie, B. N. Hu, Wenhui Liu, Luoxing Li, Congchang Xu, Pengcheng Guo
Abstract
Investigating effect of recrystallization mechanism on deformation mode and texture evolution is conducive to controlling deformation mechanism and texture in magnesium alloys under medium-high temperature impact loading. In the present study, a Johnson-Cook model incorporating twin strengthening was established to simulate macro-deformation, and a twinning induced recrystallization (TDRX) model and bulging recrystallization (GBBDRX) model are introduced into visco-plastic self consistant (VPSC) framework to quantitatively study the deformation mechanism of pre-twinned AZ31 magnesium alloy during medium-high temperature impact loading. Both TDRX and GBBDRX occur, with basal slip as the dominant slip system, followed by pyramidal 〈 c + a 〉 slip and prismatic slip. The dynamic recrystallization (DRX) significantly influences basal and pyramidal 〈 c + a 〉 slip systems, with minimal impact on secondary deformation mechanism. In addition, the recrystallization mechanism of grain boundary bowing increases the activity of basal slip and decreases the activity of pyramidal 〈 c + a 〉 slip. The nucleation and growth of recrystallized grains enhance basal slip activity and suppress pyramidal 〈 c + a 〉 slip, leading to the formation of a strong basal texture. As dynamic recrystallization progresses, a bimodal texture develops, characterized by a reduction in basal component pole density and a more pronounced basal slip.