Optimization Of GTAW Process Parameters For Joining Dissimilar Alloys, SS 202 And SS 304

Abstract

This research investigates the joining of two dissimilar stainless-steel alloys, SS 304 and SS 202, using Gas Tungsten Arc Welding (GTAW). SS 304 is widely recognized for its excellent intergranular corrosion resistance, making it suitable for applications such as pressure vessels and automotive components. In contrast, SS 202 is a cost-effective alternative with good tensile strength and toughness, commonly employed in structural applications and kitchenware. TIG welding, known for its precision and control, enhances productivity while reducing time and cost. The study utilizes Taguchi’s Design of Experiments (DOE) methodology to determine the optimal welding parameters—including welding current, root gap, gas flow rate, groove angle, and filler material—to achieve uniform tensile strength and hardness in the dissimilar weld joint. Taguchi’s orthogonal array design, combined with Analysis of Variance (ANOVA), was employed to analyze weld characteristics and optimize process parameters for improved joint performance. The optimal tensile strength (553.543 MPa) was achieved with a welding current of 160 A, gas flow rate of 3 l/min, groove angle of 60°, root gap of 1 mm, and filler material 308 L. The optimal hardness (284.99 BHN) was obtained with a current of 60 A, gas flow rate of 9 l/min, groove angle of 40°, root gap of 1 mm, and filler material 304 L. These results were further validated and compared using predictive modeling techniques, including Linear Regression, Random Forest, Artificial Neural Networks (ANN), and a Genetic Algorithm, which served as a confirmatory approach for the optimal parameter combinations. The predicted outcomes were then compared with experimental values to assess the accuracy and reliability of the models in enhancing weld joint performance