Improvement in rollability of AZ91 magnesium alloy by carbon addition

▶ Carbon addition to AZ91 alloy significantly reduces grain size from 460 mm to 75 mm. ▶ Carbon addition can remarkably improve rollability of as-cast AZ91 alloy. ▶ Refinement of initial grains changes recrystallization behavior from TDRX to CDRX. ▶ Twin boundaries within grains provide easy crack propagation routes. ▶ Transition of recrystallization behavior is a main reason for rollability improvement.