Friction stir welding of AA5083 aluminium alloy: Multi-response optimization using Taguchi-based grey relational analysis

In this research work, friction stir welding of aluminium alloy AA5083-H321 is performed for optimization of the process parameters for maximum joint strength. Taguchi’s L 9 orthogonal array has been used for three parameters – tool rotational speed, traverse speed and tool tilt angle. Multi-response optimization has been carried out through Taguchi-based grey relational analysis. The grey relational grade has been calculated for all three responses – ultimate tensile strength, percentage elongation and micro-hardness. Analysis of variance is the tool used for obtaining grey relational grade to find out the significant process parameters. Tool rotational speed and traverse speed are the two most significant parameters which influence most of the quality characteristics of friction stir welded joint. Validation of the predicted values done through confirmation experiments at optimum setting shows a good agreement with the experimental values.