The hot deformation behavior, microstructure evolution and texture types of as-cast Mg–Li alloy

Abstract

Abstract In this study, aiming to systematically investigate the hot deformation mechanism, microstructure evolution and texture types of Mg–5Li–3Al–2Zn (LAZ532) alloy, and confirm the optimum constitutive model and hot working conditions of LAZ532 alloy. The hot compression test of LAZ532 alloy was performed on Gleeble-3500 simulator at deformation temperatures and strain rates in the range of 200 °C –350 °C and 0.001 s−1–1 s−1, respectively. The experimental results showed that the established optimum constitutive model could accurately predict the hot deformation behavior of LAZ532 alloy, and the stable hot-deformation zones with peak efficiency of power dissipation were concentrated in the zones range of 300 °C , 1 s−1, 0.001 s−1–0.01 s−1 and 350 °C , 0.01 s−1–0.1 s−1, respectively. By observing the microstructure of the alloy showed that the dynamic recrystallization (DRX) mechanism could be considered to be discontinuous dynamic recrystallization (DDRX), and the recrystallization degree increases with the increasing of deformation temperatures or decreasing of strain rates. Moreover, based on EBSD analysis, it was found that both the deformed microstructure and recrystallization microstructure in the alloy had a //CD texture, and a few {10 1 ¯ 2} extension twins were observed in the coarse deformed grains.