Multiple-twinning induced recrystallization and texture optimization in a differential-temperature-rolled AZ31B magnesium alloy with excellent ductility

The effect of differential roller temperature (DTR) (low and high roller temperature difference: 60 and 180 K) on the microstructure evolution, deformation mechanism, and mechanical properties were investigated in a commercial AZ31B alloy sheet. Compared with the LDTR sample, a considerable shear strain (>0.4) in the HDTR sample led to a multiple-twinning system, especially the formation of contraction twins (CTWs) and double twins (DTWs). After annealing, the HDTR-annealing (HDTR-A) sample achieved an excellent ductility (similar to 33.6%) as a result of a higher recrystallization fraction (similar to 71.75%) and more optimized texture component (max basal texture intensity decrease from 36.13-8.06). [GRAPHICS] IMPACT STATEMENT A new method, differential temperature rolling, was used in AZ31B Mg alloy to induce multiple-twinning systems, which strongly influences the recrystallization mechanism and texture evolution, leading to a high ductility.

Automated summary

The effect of differential roller temperature on the microstructure evolution, deformation mechanism, and mechanical properties of AZ31B alloy sheet was investigated. Higher roller temperature difference led to a larger shear strain and the formation of multiple-twinning systems. The annealed sample with higher temperature difference achieved better ductility.