Defect Formation in Different Characteristic Areas During Variable-Curvature Shell Room-Temperature Stamping of Cast-Rolled AZ31 Alloy

Understanding the stamping behavior of cast-rolled AZ31 magnesium alloy sheets at room temperature is helpful to promote its deep processing application. The research object selected in this paper is a variable-curvature shell with complex geometric features. The purpose is to investigate the effects of blank shape, blank holder force (BHF), and die clearance on the formability of cast-rolled AZ31 magnesium alloy shells, and to further clarify under reasonable process conditions defects that are prone to occur in the shell characteristic areas and limit the forming height of the shells. The results show that the proportion of the safety zone is obviously affected by the process conditions. It appears that the blank shape when approaching the cross-section of the shell is beneficial to improve the safety zone ratio. When the BHF is 65 kN and die clearance is 3 mm, the safety zone ratio will reach the maximum proportion of 39.61