Investigating the effect of arc offsetting in AISI 304 stainless steel and copper welding using gas tungsten arc welding

The present study investigates the effect of welding arc offsetting on weldments of AISI 304 stainless steel and oxygen-free copper (C10200) sheets, 1.00 mm thick. A dissimilar weld joint is fabricated using the gas tungsten arc welding process. Due to the large differences in material properties, there is uneven partitioning of the heat at the joint interface in dissimilar welding. Consequently, the welding arc was offset toward the copper side. The weldments are prepared using different offsetting distances for the welding arc. The finite element (FE) formulation is developed to study the thermal behavior due to welding arc offsetting in the dissimilar weldment. In this study, the offsetting distance is considered within the range of 0.0–3.0 mm. The Time–Temperature trends and the resulting temperature contours over the domain obtained using FE analysis are compared vis-a-vis experimental observation to find the optimum values of the offset for the welding arc for this combination. The analysis revealed that AISI 304 Stainless Steel is prone to melting at lower values of the offset as compared to copper which reflects the opposite trend in higher values of offset.