Estimation of the Welding Current in Gas Tungsten Arc Welded (GTAW) Process with a Specified Width Penetration for AISI 304 Stainless Steel

Gas tungsten arc welding (GTAW), also known as tungsten inert gas welding, is now widely used in the manufacturing industry. In GTAW, the weld size, especially the weld depth, is one of the important parameters of the weld. Many studies demonstrated that the weld depth significantly affects the quality of the weld joint and is greatly influenced by the welding current. Thus, estimating the welding current value for the desired weld depth is necessary. This paper presents a method to estimate the welding current in the GTAW process with a specified width penetration for AISI 304 stainless steel with 0.8 mm thickness. The welding current determination of the GTAW process is performed by using the inverse method. In this work, the inverse method utilized is the Levenberg-Marquardt (LM) method. The advantage of the method is that the algorithm is simple, easy to apply, and has a high convergence rate. Two examples are considered to demonstrate the proposed method. The relative error between the desired width penetration of the weld value and the estimated width penetration of the weld by the LM method is very small (0.2% for case 1 and 0.08% for case 2). The results show that the proposed method efficiently estimates the welding current for a specified width penetration in the GTAW process.