Effect of pass reduction on distribution of shear bands and mechanical properties of AZ31B alloy sheets prepared by on-line heating rolling

摘要

Preheating and rolling process were simultaneously achieved by on-line heating rolling system. The effect of pass reduction on distribution of shear bands and mechanical properties of AZ31 Mg alloys sheet was investigated by analyzing microstructure and texture. With pass reduction increasing, the shear bands become denser and distribute more uniformly. In all rolled sheets, shear bands distribute symmetrically along the middle layer in the side of the sheets. With reduction increasing from 15 % to 50 %, the tilting angle between the shear bands and the rolling direction decrease approximately from 27 to 14, which is due to the higher velocity difference between surface-layer and middle-layer at higher reduction. In addition, rolled sheets show lower yield strength at higher reduction. The decrease of yield strength is due to the increase of dynamic recrystallization degree and weaker texture at high pass reduction.