Minimizing spring-back and thinning in deep drawing process of St14 steel sheets

Springback, which occurs in many cold forming processes, reduces the dimensional accuracy of the sheet metal products. On the other hand, thinning is one of the main difficulties in deep drawing process that leads to a reduced mechanical strength of the final product. In this manuscript, a numerical simulation was utilized to determine the effect of die and punch profile radii, and blank holder force on the springback and thinning percentage in deep drawing process of cylindrical parts. A full factorial design of experiment was used to specify the effects of process parameters. Furthermore, validation of the numerical results has been investigated, as compared with the same experimental results. In this regard, the angle change of the vertical walls of the cylindrical product, and the maximum thinning was measured after the process. Parameter optimization was performed to achieve the lowest springback and the minimum thinning percentage; thus, punch corner radius has been identified as the most significant effect on springback. In fact, an increased springback is observed due to an increased punch radius. Also, die profile radius has had the main parameter affecting thinning percentage.