Box-Behnken Response Surface Methodology: An Analysis of the Effect of Variations in TIG Welding Parameters on Tensile Strength and Hardness Using SUS 304 Material

This study delves into enhancing tungsten inert gas (TIG) welding using SUS 304 material to support small-scale industries. SUS 304 is a widely used material in household equipment and house fences, where TIG welding techniques are commonly employed, albeit with varying weld quality. The primary objective is to achieve the maximum tensile shear load (TS load) by applying response surface methodology (RSM). The study incorporates three input parameters: welding current, gas flow rate, and electrode diameter. Additionally, the research evaluates the impact of these parameters on hardness values measured across the welding zone, heat-affected zone, and base metal. This research endeavors to significantly advance welding techniques for thin stainless-steel materials, mainly focusing on SUS 304 stainless steel. The selection of SUS 304 (JIS G 4305) material, with a thickness of 1 mm, is based on its corrosion-resistant properties, commonly applied in domestic appliances and food industry applications requiring food-grade materials. The Stahlweld TIG 160 inverter welding machine, operating at a voltage of 220 V/50 Hz, was selected and configured for the study. The maximum TS-load results were achieved during the 12th iteration, registering a magnitude of 1393.00 kgf. Conversely, the highest hardness levels were observed across all welding regions, gradually diminishing in the heat-affected zone (HAZ) and reaching its lowest point in the base metal. The findings of this study align with the attainment of the eighth objective of the Sustainable Development Goals (SDGs), contributing to the advancement of sustainable industrial practices.