Abstract:Aimed at the high rejection ratio, poor dimensional precision and low fatigue durability for aluminum alloy complex- shaped components with a doubly curved surface, formed by conventional deep drawing and drop stamping, the hydroforming was used to investigate its formability. Based on numerical simulations and experiments, the deformation mode and the process were analyzed during hydromechanical deep drawing. The wrinkle and the fracture were discussed, and the stress state and stress value were explored in the area of defects. The results show that the reasonable chamber pressure to avoid the above defects is 10−30 MPa. According to the effects of loading paths on the thickness, a reasonable pressure of 20 MPa is determined finally.

Key words: aluminum alloy; sheet component; doubly-curved surface; chamber pressure