An analysis of springback with bifurcation behavior and its application to die design

Springback in sheet metal product makes difficulties in die design because small strain causes large displacement. Especially for the sheet metal product having small geometric constraints, springback displacement may become severe. After stamping of outer case of washing machine, a large amount of springback is observed with small geometric constraints. Also, a bifurcation takes place during the springback analysis. Figure 2 shows the springback shape of the outer case of washing machine. In order to reduce the springback displacement, the effect of tooling dimensions on bifurcation behaviour and springback displacement are investigated.