Parametric Optimization of TIG Welding Parameters for 316L Austenitic Stainless Steel Using Grey–Taguchi Method

Tungsten Inert Gas (TIG) welding is extensively employed for joining austenitic stainless steels due to its superior control over heat input and weld quality. However, weld performance is highly sensitive to process parameters such as welding current, gas flow rate, electrode–work distance, and travel speed. In the present study, a systematic experimental investigation was carried out to analyze and optimize TIG welding parameters for 316L austenitic stainless steel using the Grey–Taguchi method. An L9 orthogonal array was employed to minimize experimental runs while ensuring statistical robustness. Mechanical integrity and weld quality were evaluated through visual inspection, X-ray radiography, and metallurgical observations. Grey Relational Analysis (GRA) was integrated with the Taguchi approach to enable multi-objective optimization. The results indicate that welding current and gas flow rate are the most influential parameters affecting weld soundness. The optimized parametric combination produced defect-free welds with improved bead geometry and controlled heat-affected zone. The proposed Grey–Taguchi framework proves effective for multi-response optimization in TIG welding of 316L stainless steel.