Spot welding of Al-Cu sheets using the electromagnetic pulse for improving the quality of joints

The aim of the present research is to join Al and Cu sheets using the electromagnetic spot welding (EMSW) by placing a perforated insulator mask between the sheets. For this purpose the key parameters of voltage (V), thickness of mask (tm), thickness of driver (td) and diameter of mask hole (D) were considered in order to improve the mechanical properties of Al-Cu spot weld, simultaneously. In order to evaluate the quality of spot welds, the microstructure of weld interface was studied by optical and scanning electron microscopy (SEM). The improvement of mechanical properties of Al-Cu spot welds was achieved by applying the optimal values of significant parameters. The microstructure analysis of Al-Cu spot weld at the desirable values of parameters indicated that the interface defects and intermetallic layers were reduced to a minimum value.