Optimization of process parameters of metal inert gas welding with preheating on AISI 1018 mild steel using grey based Taguchi method

Welding processes form an integral part of manufacturing industries and construction works. Among all the welding processes available, MIG welding is the widely used welding process due to its versatility and higher productivity. In this research work, AISI 1018 mild steel samples have been welded in V-butt joint configuration using MIG welding. The design of experiment is Taguchi based Orthogonal Array (L-9). Effect of process parameters such as current, voltage and preheat temperature has been studied and welds are examined using X-ray radiographic tests. Weld quality has been assessed in terms of tensile properties of weldments such as ultimate tensile strength and percentage elongation. Process parameters have been optimized using grey based Taguchi methodology. Further, analysis of variance has been done to ascertain the influence of input parameters on response parameters. Experimental results show that to achieve optimum ultimate tensile strength and percentage elongation of weldments, preheat temperature turns out to be the most effective input parameter followed by welding current and voltage. A mathematical model has been developed using multiple regression equations. In the end, a confirmatory experiment with optimized parameters from the analysis has also been performed to confirm the results. (C) 2019 Elsevier Ltd. All rights reserved.