Application of Grey-based Taguchi Method For Optimising Gas Metal Arc Welding Of Stainless Steels

Gas Metal Arc Welding (GMAW) is widely used in industry to obtain high quality welds with high deposition rate. Carbon di-oxide is used in this work for GMAW, the process known as metal active gas (MAG) welding. In this experimental investigation, 1.2 mm diameter of stainless steel electrode is employed maintaining a ischolar_main gap of 1.3 mm and 15 bar gas pressure. Welding voltage, welding current, and welding speed are varied to weld stainless steel specimens to make square butt joint. Experimental design is made using Taguchi's L9 orthogonal array design, and signal-to-noise ratio is used to derive objective functions to be optimized within experimental domain. Objective functions selected include weld bead reinforcement, depth of penetration, weld metal hardness and bending load at a bend angle of 100. Grey relational analysis is applied to solve this multi-response optimization problem. Within the experimental domain, optimum weld is found with a weld current of 160 amp and a weld voltage of 30 volt with 327 to 554 mm/min weld traverse speed.