Multi-response mathematical modelling, optimization and prediction of weld bead geometry in gas tungsten constricted arc welding (GTCAW) of Inconel 718 alloy sheets for aero-engine components

The gas tungsten constricted arc welding (GTCAW) parameters namely Main Current, Delta Current, Delta Current Frequency and Welding Speed were optimized to obtain full penetration and optimum weld bead geometry using Response Surface Methodology (RSM) to join thin Inconel 718 alloy sheets (2 mm thick). Empirical relationships were formulated to predict the weld bead characteristics such as width of bead, depth of penetration, width of heat affected zone (HAZ) and area of fusion zone (FZ). The weld bead characteristics were predicted with good accuracy using developed empirical relationships. The direct and interaction effect of GTCAW parameters on weld bead geometry is discussed in this paper.