Effect of Interlayer Composition on the Microstructure and Mechanical Properties of 1050 Aluminium to St14 Carbon Steel Joint Via Resistance Spot Welding Method

In this study, the bonding of 1050 aluminum alloy to St14 carbon steel was investigated by resistance spot welding. The variable parameters in this process were the holding time of the jaws, the power of the device and the type of interface layer to be placed between the two alloys. Aluminum powder was used as the interface layer. After welding, appearance check, shear test, microstructure and microhardness were performed. results of EDS analysis in the weld zone showed that different intermetallic compounds were observed. The thickness of the intermetallic layers that created depended on the duration of the welding process and also the intensity of the applied current in the process. The results of shear test showed that the highest shear strength among all joined sample was related to the joined sample in 7 seconds with a power of 2.5 kW and the interface layer containing 0.1% boron. The results of microhardness test showed that the highest amount of microhardness in the welding center was related to the joined sample in 7 seconds and the power of 2.5 kW was 116.9 Vickers.