Process Parameters Influence the Mechanical Properties and Nugget Diameter of AISI 316 Stainless Steel During Resistance Spot Welding

Abstract

Resistance spot welding (RSW) is an important fusion welding process used in many applications, including storage tanks, pipes, and medical tools. For this, should be improved the joints and developing the process parameters and through this research will be discussed the results and concept development. Herein, 1 mm-thick AISI 316 austenitic stainless steel was welded by RSW, and the effect of the welding process parameters, such as “welding current, pulses, squeeze time, and welding time”, on the mechanical properties, nugget diameter (ND), and microstructure of AISI 316 were investigated. As a result, there was a direct relationship between shear-tensile force and ND. The maximum shear-tensile force (12.5 kN) was obtained using 7500 A, 3 pulses, 1.8 s squeeze time, and 1 s welding time. The ND was maximized using 7500 A, 3 pulses, 1.6 s squeeze time, and 0.8 s welding time. The DOE analysis gives an indication about the relation between the parameters and ND on the hand and the parameters and shear strength on the other hand. The microstructure was investigated by optical microscopy, revealing the presence of martensitic, widmanstatten austenite, and ferrite structures.