Similarity and Dissimilarity in Optimization of Welding Parameters for Austenitic and Ferritic Stainless Steel GTA Welds Using Taguchi Method
Abstract
Gas Tungsten Arc Welding (GTAW) is very beneficial for the structural and chemical sectors for joining stainless steels because of its enhanced quality and controlled heat input. Welded structural joints rely on the optimization of GTAW process parameters. The present work studies the comparative optimization behavior of GTAW joints made with austenitic stainless steel (AISI 304) and ferritic stainless steel (AISI 430). The influence of filler metal type, welding current, Arc Voltage, Shielding Gas flow rate, and heat input on tensile strength, microhardness, and resistance to pitting corrosion was studied using the Taguchi L18 orthogonal array method. In order to determine critical process parameters, ANOVA and regression analysis were used. Microstructure characterization was done using optical and scanning electron microscopes to study the grain structure and phase morphology in the weld. The corrosion resistance and mechanical response of a weld are determined by the composition of the filler metal more than the welding parameters. The improved behavior of the welds using similar parameters for different configurations is discussed.
Keywords
: GTAW, Welding optimization, Taguchi method, Similar welding, Dissimilar welding, Stainless steel, ANOVA.