Ameliorating the edge cracking behavior of Mg-Mn-Al alloy sheets prepared by multi-pass online heating rolling

Low-cost Mg-1Mn-0.5Al (MA10) alloys with good comprehensive strength and ductility have been developed and have the potential to substitute commercial AZ31 alloys. Thus, the rollability in terms of the edge cracking behavior of MA10 alloy sheets was investigated by multi-pass online heating rolling at different temperatures. The microstructure evolution was characterized by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The results reveal that edge cracking is significantly improved with increasing temperature due to the more uniform microstructure, higher degree of recrystallization, more homogeneous strain distribution, and more activation of non-basal slips at the edge. The maximum basal texture intensity at the edge of MA10 rolled sheets is obviously increased with increasing temperature, which can be attributed to the increased numbers of grains with basal orientation after multi-pass online heating rolling.