Automatic determination of non-uniform blank-holder force in sheet metal forming

The blank-holder force is an important and influential parameter in the sheet metal forming process. The size of this force around the part can be very effective in eliminating the defects of fracture and wrinkling in different points of the part. In symmetrical axial parts, a suitable uniform blank-holder force can prevent both defects, but for asymmetric axial parts, it is usually difficult to achieve a suitable uniform blank-holder force. In this case, the non-uniform blank-holder force can have a significant effect on improving the quality of parts. It is clear that simulation of the sheet metal forming process in finite element software and the effective use of optimization algorithms can be of great help in determining the amount of non-uniform blank-holder force. In this research, a method for automatic determination of non-uniform blank-holder force is presented. In this method, which has been created with the help of Catia, Abaqus, and Modefrontier software, various simulations and change of input parameters are performed completely automatically, until the appropriate conditions for sheet metal forming are determined. To show how this method works, two pieces with different geometries were examined. In these two geometries, it was not possible to achieve a piece without fracture and wrinkling with uniform blank-holder force, but the results showed that using this method, a suitable non-uniform arrangement of blank-holder force can be achieved automatically, which produces a flawless piece.