Tailoring the Texture and Mechanical Properties of Textured-AZ31 Mg Alloy Sheets by Twinning and Recrystallization

Abstract

In this study, a method of corrugated width limit alignment processes (CWLA) was applied to pre-twin in hot-rolled Mg alloy sheets. The microstructure evolution and mechanical properties of the CWLA sheets were studied. The results demonstrated that the grain orientation was transformed from strong basal texture to RD-rotated texture after CWLA treatment and up to 22.2% of {10–12} tensile twin boundaries were produced in the microstructure. The 60 ± 5° < 10–10 > twin variant pairs were dominant in the twinned microstructure. Two kinds of dynamic recrystallization (DRX) mechanism, i.e., continuous DRX (CDRX) at low-temperature CWLA and the discontinuous DRX (DDRX) at high-temperature condition were observed. After post-annealing, the twin-induced static recrystallization (SRX) and abnormal grain growth were observed in the CWLA samples, and most twin boundaries were retained. After CAWL for 60 min at 300 °C and post annealing, an improvement on plasticity and strength were achieved with 55% increment for uniform elongation (UE) and 10% increment for ultimate tensile strength (UTS).