Taguchi-based Optimization of Process Parameters for Quality Weld of Tungsten Inert Gas Bead-on Plate Welding on Low Carbon Steel

It is of great significance to select appropriate welding process parameters and their limits for quality weld in any welding process. Optimization of any welding process variables is markedly difficult because welding is a multi-factors process, which is impacted by lots process unpredictability. In this study, a multi-response optimization process has been applied for Tungsten Inert Gas (TIG) bead-on plate welding on low carbon steel. Taguchi's method has been introduced for the designing of experiments with the intension of reducing the number of experimental runs. Three welding process parameters-current (I) from 130-190A, traverse speed(S) 0.30-0.75 m/min and gas flow rate (Gf) 12-18 lit./min with a constant voltage 25 V were considered in this analysis. The weld bead geometry viz. weld penetration, weld bead width or thickness and haz (heat affected zone) thickness were measured and also investigated the grain sizes and hardness of haz. The ANOVA (analysis of variance method) has been introduced to assess the significance of the parameters on overall quality of the weldment. It shows the workability of the Grey-based Taguchi method in manufacturing world for ongoing development in product quality. It has been noticed that the process variables were seriously impacted on weld bead as well as hardness and grains size of the haz.