Analytical method for prediction of weld line movement during stretch forming of tailor-welded blanks

Tailor-welded blanks (TWBs) consisted of metal sheets with different characteristics welded into a single flat blank prior to pressing in order to achieve the optimal material arrangement and weight reduction for cars, and to increase machine flexibility and process efficiency. The movement of weld line in TWBs is always a challenging issue during manufacturing process. In this research, a new analytical method for prediction of weld line movement in TWBs is developed. A comparison between the analytical results with those obtained from finite element simulation as well as the experimental data indicates good compatibility between the predictions of the developed method in the case of both weld line movement and dome height of TWBs. Furthermore, the developed analytical method can appropriately consider the effect of thickness ratio on both weld line movement and dome height. It was observed that weld line movement increases as thickness ratio enhances.