Effect of Hot Compression Process on Recrystallization Microstructure and Mechanical Properties of AZ31 Magnesium Alloy

Hot compression deformation was exerted on AZ31 magnesium alloy from 200°C to 420°C with the different reduction from 10% to 50%, and the effects of deformation temperature and reduction on dynamic recrystallization were studied. The results show that the recrystallization behavior happened in specimens after hot compression deformation. Deformation twin belts crossed in the grain when specimens were deformed at low temperature, and fine recrystallization grains formed in the deformation belts. As temperature rising, the deformation twin belts disappeared, while recrystallization was sufficient and the distribution of grains size was uniform, and the grain grew up with the increasing of temperature. In addition, the work hardening weakened by recrystallization softening. When the specimens were deformed at 320°C under different deformation reduction, the deformation strengthening was still reserved partly. Dynamic recrystallization occurred only in the deformation belts when the specimens were deformed under small deformation reduction. With the deformation reduction increasing, the nucleus of recrystallization increased, and dynamic recrystallization got sufficient, and the grains became fine and uniform.