Modelling and Optimization of Dissimilar Welding Between 304L and HSLA-X70 Using Response Surface Methodology

The industrial applications of TIG welding process are based on the choice of suitable input values for welding parameters like current, speed and gas flow, which determine mechanical properties of weld joint the like tensile strength. Welding parameters were measured according to 33 full factorial parameter designs with independent variables of TIG dissimilar welding process between austenitic stainless steel 304L and a high strength low alloy steel HSLA-X70. The response surface methodology (RSM) and analysis of variance (ANOVA) were used to check the validity of quadratic regression model and to determine the significant parameter affecting the output responses. The results show that tensile strength is influenced principally by welding speed. Finally, the ranges for best welding conditions are proposed for serial industrial production.