Dynamic recrystallization behavior and texture evolution during extrusion of Mg–2.0Y–2.0Zn–2.0Al–0.3Mn alloy

Abstract

This work investigated the microstructure evolution behavior of the Mg–2.0Y–2.0Zn–2.0Al–0.3Mn alloy within the initial plastic deformation zone, the plastic deformation zone prior to the die exit, and the non-plastic deformation zone after the die exit during the extrusion process. The results showed that in the initial plastic deformation zone, basal <a> slip dominated the plastic deformation of the alloy, accompanied by a relatively high basal texture intensity. The alloy mainly consisted of larger deformed grains and smaller dynamically recrystallized grains, and the dynamically recrystallized grains mainly nucleated and grew through discontinuous dynamic recrystallization. From the initial plastic deformation zone to the plastic deformation zone prior to the die exit, non-basal slip gradually became activated and dominated the plastic deformation of the alloy. Meanwhile, continuous dynamic recrystallization gradually dominated the formation of dynamically recrystallized grains, and the increase in the recrystallization degree led to the weakening of the basal texture intensity. In the non-plastic deformation zone after the die exit, static recrystallization took place in the alloy, further reducing the basal texture. At the same time, grain boundary migration and grain growth caused a certain degree of deflection in grain orientation, and some grains with <0001>//ED orientation showed a relatively obvious growth advantage.