Selection of upper electrode tips for the resistance projection welding of M12 T-shape weld nut and SGHC Hot-dip zinc-coated steel sheet

Abstract

Objective of this research is to select the geometry of the upper electrode tip used in the resistance projection welding (RJW) of weldment between M12 T-shape weld nut and SGHC Hot-dip zinc-coated steel sheet. The projection welding was performed using a 50 kVA AC device, 50 Hz RJW machine, while the quality of the weld was assessed by considering the weldment appearance and maximum compression force. The results of the study explained the weldment appearance of both top surfaces of the M12 T-shape weld nut and the surface of the SGHC Hot-dip zinc-coated steel sheet and maximum compression force for all welds with the various different heat input. The electrode geometry type 3 was achieved acceptable good weld quality and the maximum compression force is able to achieve the desired quality requirements in the projection welding process.