Investigation of the mechanical properties of AA6061, AA5052 aluminum alloys joined with AISI 304L stainless steel using pressure welding

In today's engineering and industrial applications, the joining of dissimilar materials to harness their superior properties while also achieving cost advantages is becoming increasingly important. One of the commonly used welding methods for joining dissimilar metals is resistance spot welding in metalworking and industrial applications. To obtain the desired mechanical properties from the weld joint, it is essential to improve the quality and microstructure of the welding. These improvements can be achieved, especially by accurately determining welding parameters. In this study, different thicknesses of 304L austenitic stainless steel were joined with 5052 and 6061 aluminum alloys using the resistance spot welding method at different welding current parameters. During the welding process, welding current values 5 kA, 5.5 kA, and 6 kA were applied. Other important welding parameters such as electrode pressure and welding time were kept constant. To evaluate the mechanical properties of the materials after the welding process, tensile tests and microhardness measurements were conducted. Additionally, the welding zone was examined with scanning electron microscopy (SEM) images. The mechanical and metallographic properties of the weld joints were thoroughly evaluated to understand the effects of welding current on these connections. Based on the experimental results, it was observed that the tensile strength increased as the welding current increased. The findings in this thesis can contribute to the development of more effective and optimized processes for welding different materials. Consequently, by enhancing mechanical properties, industrial welding applications can be made more efficient and reliable. Keywords: Welding of dissimilar metals, 304L stainless steel, 5052 aluminum alloy, 6061 aluminum alloy, resistance spot welding, tensile strength, microhardness.