Effect of Heat Source Positioning on Hybrid TIG-MAG Arc Welding Process

Hybrid TIG-MAG Arc Welding implies the two conventional arc welding processes combine to provide a more improved outcome overcoming their limitations at the individual level. The hybridization demands the favorable interaction of the participating heat sources to produce an effective coalescence. The participating heat sources interact in harmony when positioned optimally to enter each other's domain of influence in the synergistic manner. This study is an attempt to investigate the effect of positioning of heat sources on the hybrid arc welding process in terms of the achieved weld penetration for the bead on plate welding of mild steel. The study presents special welding torch geometries for easy location and clamping on an indigenous fixture which forms an automated assembly to carry out the devised hybrid arc welding process. The study identifies torch angles, arc lengths and the arc separation as the 5 parameters critical in positioning of the heat sources. Torch angles have been optimized through a 2-stage preset experimentation. The arc lengths and the arc separation have been optimized considering 4th order parameter interactions in a quadratic through a designed experiment by analyzing the generated response surfaces and the parameter interaction profile. (C) 2018 Elsevier Ltd. All rights reserved.