A parametric study on the mechanical properties of MIG and TIG welded dissimilar steel joints

In the present day, the joining of dissimilar metals used in the same industry applications is of great interest. MIG and TIG welding processes are among the most common methods used to join dissimilar metals with high strength and reliability. Due to the different mechanical properties of dissimilar metals to be joined by these welding methods and welding parameters, they must be carefully selected. In this study, the effects of Total Accumulated Weld Volumes (TAWV) and different groove angles (45 degrees, 60 degrees, 75 degrees and 90 degrees) on the mechanical properties of AISI 1040 and AISI 8620 cylindrical steel joints were investigated experimentally. In addition, the fracture surfaces of the samples were examined by scanning electron microscopy (SEM) and energy dispersive X-ray (EDAX). In the process with MIG and TIG welding, only current and voltage changes were made in order to measure the effects of parameters on the mechanical properties of the joints more clearly. As a result of the studies, the highest average Ultimate Tensile Strength (UTS) was 579.611 MPa and the lowest average UTS value was 424.611 MPa. Based on TAWVs, the highest average UTS value was obtained in TIG welded joints, and the lowest average UTS value was obtained in MIG welded joints. It was observed that the UTS values of the joints were positively affected by the increase in TAWV. The UTS value of the 90 degrees groove angled joint was found to be 40.25% higher than the UTS value of the 45 degrees groove angled joint.