Research on microstructure evolution and deformation behaviors of AZ31 Mg alloy sheets processed by a new severe plastic deformation with different temperatures

In this paper, AZ31 Mg alloy was fabricated by a new severe plastic deformation with different temperatures. Microstructure, texture, and hardness were investigated by the several characterization methods. The results show that effective-strain gets larger as the temperature drops, which is the same as the grain refinement effect. Meanwhile, pyramidal < c + a > slip activates more frequently at higher temperature, and plenty of {10−11} contraction twins arise, which is devoted to triggering pyramidal < c + a > slip, effectively weakening basal texture. Besides, dynamic recrystallization (DRX) has occurred, but it may not have happened fully, and the main fraction of grains are sub-structured grains. Finally, at 200 °C, the hardness can reach 79.9 HV, but the hardness distribution is the worst because an internal crack might occur, compromising hardness uniformity, while the hardness values at 400 °C are too low but more steady.