Grain refinement due to complex twin formation in rapid hot forging of magnesium alloy

Twinning behavior and twin interactions were investigated to characterize grain refinement in magnesium alloys subjected to rapid hot forging. Formation of {101¯2} tensile twins with various twin variants and their subsequent mutual interaction resulted in new boundaries at low strain. With further straining, fragmentation of {101¯1}-{101¯2} double twin bands by the formation of more complex twins in the interior, accompanied by a drastic decrease in the stored energy, led to grain refinement.