Multi response Optimization of Welding Parameters in Dissimilar Plasma Arc Welded Joints Using RSM Based GRA Coupled with PCA

The quality of the joints is essential to achieve customer satisfaction and earning profit in manufacturing industries. This work investigates the multi-response optimization of the plasma arc welded (PAW) process parameters of the dissimilar Ti-3Al-2.5V titanium alloy and AA8011-H24 aluminium alloy joints using RSM based GRA coupled with PCA. The principal component analysis is incorporated into the response surface methodology based grey relational analysis to achieve the optimum responses viz., tensile strength and tensile elongation with the welding parameters, viz., welding current, torch angle, gas flow rate and welding speed of the PAW joints. The response surface and contour plots are used to study the effect of parameters of the joints. The welding speed is the most significant parameter on the composite welding quality index (CWQI) followed by welding current, gas flow rate and torch angle to decide the quality of the joints at the optimal levels.