Abstract
In recent years, the use of aluminum alloys in the automotive industry has been increasingly promoted to achieve lightweight vehicle bodies. Meanwhile, resistance spot welding (RSW) has long been widely employed for automotive body assembly, and thus considerable efforts have been devoted to improving the weldability of aluminum alloys by RSW. In particular, the stability of nugget formation, i.e., the molten region, during consecutive welding has emerged as a critical technical challenge. In this study, electrode wear, which is a key factor influencing nugget formation, was investigated to improve the continuous spot weldability of aluminum alloys. The relationship between the extent and morphology of electrode wear and nugget formation behavior was systematically examined. Furthermore, the electrode wear morphology that enhances continuous weldability was identified. The results revealed that stable nugget formation during consecutive welding requires the generation of sufficient heat at the center of the joint during the initial stage of current flow. Moreover, it was demonstrated that achieving such heat concentration at the joint center necessitates maintaining electrode wear as uniform as possible.
Showing the abstract — retrieve the full paper via the Exa API.