An analytical solution to springback of sheet metals stamped by a rigid punch and an elastic die

Springback is one of the fundamental factors affecting the quality of a stamped component. It has been recognised that springback can be controlled more easily when using an elastic die in a stamping process. However, the deformation of the die introduces more complex mechanisms of springback and an in-depth understanding of such processes is still lacking. This paper developed an analytical solution to the springback of sheet metals stamped by a rigid punch and an elastic die under plane-stress deformation. The stamping process was modelled as a three-body contact problem. The sheet workpiece was divided into three parts according to its contact with the punch and die. The workpiece material was considered to be elastic/perfectly plastic. Based on the solution obtained, the effects of the most important processing factors, namely the friction between the workpiece and die and the elastic properties of the die, were examined. The solution shows that a no-springback stamping process can be achieved by a comprehensive selection of processing parameters.