Investigation in to GTAW with alternating shielding gases on weld metal properties of SS304 stainless steel

Abstract

In this research work, stainless steel 304 Grade metal with 5mm thick plate were used for investigating weld penetration and weld bead using GTA welding. The shielding gas supplied alternatively with variation of timing. The weld joint were performed with 10 mm thick plate with 12 passes of alternate supply of shielding gas with variation in timings. This work mainly focus on effect of alternate supply of shielding gas for pure Argon, pure Helium and combination of Argon and Helium. Various process parameters are taken to constitute L9 orthogonal array for weld penetration, and L27 orthogonal array for weld bead. Three weld joints with each 12 passes of alternate supply of shielding gas with pure Argon, Helium and combination newlineArgon and Helium were formed. Optimization techniques like ANOVA and Genetic algorithm were used to find the influencing parameter .The mechanical tests like hardness, tensile and impact test were performed. The metallographic analyses for micro and macro structures were studied using Optical microscopy (OM), Scanning Electron Microscope (SEM) and Energy dispersive X-Ray analysis (EDAX). newline newline