Grey based Taguchi method for multi-response optimization of FSW of aluminium AA 6061 alloy

Research presented an experimental investigation to determine the optimal parametric setting during friction stir welding (FSW) of Aluminium AA 6061 alloy. Three critical parameters viz. welding speed, axial force and tool rotational speed at three different levels are taken as the input processing parameters. Experimental runs were designed using Taguchi L9 orthogonal array. Selected process parameters and their levels were chosen after conducting the pilot experiments and also through the literature survey. Based on the importance, tensile strength and tensile elongation are the output quality characteristics considered. The significant process parameters that affect welding performance were determined using the analysis of variance (ANOVA) and F-test in conjunction with the experimental results obtained. Process parameters such as welding speed and Tool rotational speed are found to be the most significant parameters affecting grey relational grade. Considering the significant parameters so obtained, improvement in the quality characteristics for the FSW of Aluminium AA 6061 was done and the improved results were obtained when compared to the original parameters. Multi response optimization was performed on both the output responses using the Taguchi-Grey relational analysis.