Study the effect of Welding Current on the microstructure and strength of dissimilar weld joint AISI 303/AISI 1008

The welding of metals is one of the most important processes that require high control for obtaining a good quality of weldments. The joining of dissimilar metals is a more complex operation compared to the joining of similar metals due to the differences in physical metallurgical and mechanical properties. In this article, austenitic stainless steel AISI 303 stud was welded to low carbon steel AISI 1008 plate using arc stud welding (ASW) process. An experimental procedure was applied to estimate the effect of welding parameters namely welding current and welding time on the microstructure and mechanical properties of the joint. The optical microscope V83MC50 was used to show microstructure properties while both the micro-Vickers Hardness and tensile test were adopted to evaluate the mechanical properties. The results revealed that the presence of carbides at the fusion zone FZ towards AISI 303 leads to the maximum value of hardness (501) HV. The best welding parameters were 600 AMP 0.25 second at which joint strength of 515 MPa was recorded. Welding time was the most important parameter in the ASW process followed by welding current, proper selection of welding time, and current welding produces good joint quality