H. Abedi Chermahini, M. Piran, A. Esmaeili Chamgordani, M. Atapoor,
Volume 10, Issue 2 (12-2024)
In this research, the mechanical and microstructural properties of AISI 316L sheets welded by RSW method using copper interlayer were investigated. In this regard, two types of connections were made, one without the use of an interlayer and the other with the use of a copper interlayer in different currents. In order to choose the optimal current for both types of connections, tensile tests were first performed, and microstructural, microhardness, elemental evaluation and failure mode tests were conducted on the selected samples. According to the obtained results, by increasing the electric current, the heat input in the welding pool is sufficiently high and the microstructural and mechanical properties of the welding zone were improved(Conversion of coarse grain to fine grain). Also, due to the optimality of the electric current in both samples with and without the interface layer, both samples had environmental failure, which indicates the high strength of the interface and their welding point. Changes in the chemical composition in different welding zones were insignificant and the distribution of elements was uniform in all zones. Also, the hardness changes from the base metal to the center of the welding zone were in the order of welding zone > base metal > heat-affected zone, which was consistent with the results obtained from the microstructural investigations. According to the results obtained for both cases with and without the use of an interface layer, the resistance spot welding method showed a successful connection for both types of cases.
