Evaluation of Consecutive Resistance Spot Welding Performance in Aluminum Using Multi Ringed Dome Electrodes

In resistance spot welding of aluminum alloy sheets for automobile bodies, dome radius-shaped electrodes and radius-shaped electrodes are commonly used. Recently, especially in the United States, electrodes with multiple concentric grooves etched into the tip of dome radius-shaped electrodes have been adopted. Basic investigations of MRD electrodes have reported on appropriate current ranges, strength characteristics, and changes in weld diameter and appearance associated with continuous spot welding. In this study, in addition to that, the surface quality changes caused by continuous spot welding were experimentally examined and compared with the results of DR radius electrodes. As a result, it was found that the surface quality with concentric grooves is better in terms of continuous spot weldability when using MRD electrodes.