Rolling texture development in a dual-phase Mg-Li alloy: The role of temperature

Dual-phase Mg-Li alloys sheets were rolled at four different temperatures ranging from liquid nitrogen to 300 ℃ to explore effect of rolling temperature on texture and mechanical properties of the material. Crystal plasticity simulation was utilized to illustrate the influence of slip activity on rolling texture development. The results show that the rolling texture is largely depended on deformation temperature. Unlike commercial Mg alloys, the critical resolved shear stress of basal slip in α-Mg phase of Mg-Li alloy decreased more significantly by increasing temperature compared to that of pyramidal <c+a> slip. Enhancement of basal slip by increasing temperature triggered a decrease of split angle of basal poles for the double-peak texture. Prismatic <a> slip largely enhanced by increasing temperature upon 200 ℃, which induced a wider orientation spread along the transverse direction. For the β-Li phase, the promotion of {110}<111> slip system at elevated temperature triggered the enhancement of {211}<110> and {111}<211> texture components. The cryo-rolled sample exhibited the highest strength compared to the others due to a strong hardening behavior at this temperature. A two-stage hardening behavior was observed in these as-rolled dual-phase alloys. Strain transition at phase boundaries could be the reason for appearance of this two-stage hardening.