Influence of zinc on mechanical behavior of resistance spot welding of aluminum and stainless-steel

This study aimed to investigate the strength of the resistance spot welded joints of dissimilar materials with or without filler. This research used 1mm thickness Ferrite 430 Stainless Steel and 1.2mm thickness 6019 series Aluminum with 0.2mm thickness Zinc (Zn) as the filler. The specimens were divided into two groups, namely with filler and without filler group—with current variations of 6000 A, 7000 A, and 8000 A. Meanwhile, weld time variations were 0.2s; 0.3s; and 0.4s. The shear strength and Micro-Vickers hardness test were performed to determine the mechanical behaviors of welded joints. The results showed that the addition of zinc filler metal with variations of current and weld time significantly affects the strength of welded joints. Furthermore, the hardness test showed that there is a significant increase in hardness at the weld joint region compared to the parent metal. The optimal strength occurred on specimens using zinc filler metal at current variations of 8000 A and weld time of 0.4s with a value of 1235.165 N. Meanwhile, the highest hardness value was obtained by metal region of weld specimen (nugget) using filler with current of 8000 A and weld time of 0.4 seconds.