Determination of optimal resistance spot welding parameter on low carbon steel welding quality

The welding quality in the form of nugget diameter and the tensile strength of resistance spot welding in low carbon steel was experimentally investigated. Two types of low carbon steel; the uncoated plate of SPC 270D and the coated plate of SCGA 270D with the same thickness of 0.7 mm were used and studied in this experiment. The process determination of optimal welding conditions was done based on welding current and welding time for the combination of each material and also their mixed. This work revealed that both of the weld current and weld time parameters have a great influence on the quality of the spot welded joints, in the form of nugget diameter formation and its corresponding tensile shear load. The latter is needed to be examined in order to understand the failure mode of joints. The results which plotted as graphs and the confirmation by figures are discussed.