Microstructure and texture evolution of AZ31 magnesium alloy during rolling

The production of magnesium alloy sheets normally involves several processing stages including hot rolling, cold rolling and intermediate annealing. The microstructure and texture evolution of AZ31 magnesium alloy sheets in different processing states were investigated by optical microscopy and X-ray diffraction technique. It is found that the microstructure of hot-rolled sheets is dominated by recrystallized equiaxed grains, while that of cold-rolled sheets is dominated by deformation twins. With final annealing applied on the cold-rolled sheets, fine recrystallization grains are obtained and ductility of the samples is increased. It is also found that the texture of magnesium alloy sheets prefers the basal texture, and other compositions of texture are relatively weak. Moreover, final annealing does not significantly affect texture distribution. The results of this study provide useful guidelines for optimizing the processing of magnesium alloys.