ASSESSING THE EFFECTIVENESS OF SOFT COMPUTING TECHNIQUES IN DETERMINING OPTIMAL WELDING PARAMETERS FOR REDUCED ENVIRONMENTAL IMPACT IN A COLD METAL TRANSFER WELDING PROCESS — A GREEN WELDING APPROACH

Abstract

The increasing demand for high-quality welds in various industries such as automotive, aerospace, and shipbuilding has led to the need for more efficient welding processes. Cold Metal Transfer (CMT) welding offers several advantages over traditional welding methods. This study investigates the CMT welding process applied to High-Strength Low-Alloy (HSLA) steel plates, focusing on optimizing weld parameters for enhanced joint quality and mechanical performance. The CMT process was selected for its ability to provide low heat input, thereby minimizing thermal distortion, and preserving the mechanical properties of the HSLA material. Key welding parameters, including welding speed (10–30[Formula: see text]mm/s), wire feed rate (2–4[Formula: see text]m/min), heat input (1.8–2.4[Formula: see text]kJ/mm), arc voltage (12–16[Formula: see text]V), and gas flow rate (3–5[Formula: see text]L/min), were systematically varied to assess their impact on weld integrity and strength. Uncertainty analysis is conducted and came out to be 3.25% which lies in an acceptable range. The AHP–TOPSIS analysis was conducted to identify the most important welding process parameters and equipment for achieving high-quality welds in CMT welding of steel. The results showed that welding speed, wire feed rate, and gas flow rate were the most important process parameters for achieving high-quality welds. In the AHP analysis, Tensile Strength achieved the highest priority (39%) while Impact Toughness (22%) followed it. After prioritizing the variables, an inter-relationship between the most favorable inputs with outputs is established using Artificial Intelligence (AI). Prediction analysis is performed to establish the most optimal welding setting among thousands of input sets. The sample with set 1 was found to be the best choice for producing high-quality welds in CMT welding of steel. The optimal parameter values were found to be a welding speed of 25[Formula: see text]mm/s, wire feed rate of 3[Formula: see text]m/min, arc voltage of 12[Formula: see text]V, gas flow rate of 5[Formula: see text]L/min, and heat input of 1.5[Formula: see text]kJ/mm yielding a tensile strength of 460[Formula: see text]MPa, hardness of 42[Formula: see text]HRC, impact toughness of 29 J, radiation of 110[Formula: see text]W/m2, convection of 90[Formula: see text]W/m2, and conduction of 150[Formula: see text]W/m2. This study provides valuable insights into the effective use of CMT for welding HSLA steel, offering practical guidelines for achieving high-quality welds in structural applications.