Numerical simulation of the effects of the space-variant blank-holder force and geometrical variables in the deep-drawing process

The increase in quality requirements for the formed products makes it desirable to find an effective way of controlling the process to achieve complex shape products without defects. It has been proven by many researchers that the space-variant blank-holder force can improve the quality of forming to achieve a targeted shape product (no wrinkling, a high drawing depth, less variation in thickness, etc.). In the forming process, the most common problems, tearing and wrinkling, generally result from the strain condition. In this paper the effect on the strain path with various types of space-variant blank-holder force and other geometrical parameters, such as the fillet radius, the blank size, and the clearance between the die and the punch, were compared and analysed. The results showed that the space-variant blank-holder force and some geometrical parameters affect the strain distribution to various extents during the forming process. The parameters influence the negative minor strain much more than the maximum major strain.