Numerical simulation and experimental verification in the use of tailor-welded blanks in the multi-stage stamping process

Various social requirements have extended the use of tailor-welded blanks in the automotive industry. The welding of blanks with different material grades, thickness, strength and coatings had introduced many challenging formability problems for the stamping process of tailor-welded blanks. However, in some situations the multi-stage process is a very effective solution for the stamping of tailor-welded blanks with a relatively lower formability than that of homogeneous blanks. In this paper, the numerical simulation and experimental verification, the forming of a longitudinal rail are carried out to predict the metal flow and manufacturing defects of tailor-welded blanks in the multi-stage stamping process. It can be seen that the weld on the flange region of the longitudinal rail moves towards the base material, with thicker gauge, during the stamping process. In the multi-stage process, the change of strain path will be beneficial to the reduction of strain peaks and the utilization of the potential plasticity.