Influence of geometric parameters on weld line movement in the selective heating of tailor welded blanks

Abstract

Weld line movement is one of the primary concerns encountered by automotive manufacturers involved with the stamping of tailor welded blanks (TWBs). It contributes to tearing, wrinkling and distortion in components. The objective of this research is to determine the most important factors among thickness ratio, weld line offset and temperature influencing the weld line movement of TWB. In order to reduce the undesirable weld line movement during the stamping process, a new method involving localized and controlled heating of the stronger material side has been implemented. The stamping experiments were conducted on TWBs in an electronically controlled hydraulic press. Based on the stamping results, it is found that the thickness ratio has the greatest influence on the weld line movement at room temperature followed by weld line offset. However, at elevated temperatures, selective heating of stronger material played a significant role in minimizing the weld line movement. A combined approach involving all the three factors viz. temperature, weld line offset and thickness ratio is also investigated where several options in controlling the movement of weld line were explored.

Keywords:

• Tailor welded blank
• simulation
• stamping
• selective heating
• weld line movement