Optimal parameter determination on friction stir welding process of aa6061 using grey taguchi method

Abstract

The Friction Stir Welding (FSW) process is an innovative technique to join metals in the plasticity field, thus not reaching the melting temperature and consequently the liquid state as it happen in traditional welding processes. This feature of the FSW proved an enhancement of the fatigue behavior and strength of the joints, leading some companies to adopt the process for the manufacturing of airplanes fuselages and cryogenic tanks for Space launch vehicles. The ultimate goal of this paper is to determine the optimal influencing parameter of Friction Stir welding process using Taguchi method of optimization. Here we used L9 Taguchi orthogonal design for designing the experiment. Three major controllable parameters are welding speed or feed, rotational speed and length of the tool pin are used for the present work. To convert the multi objectives like Tensile strength and the Hardness of the welded work pieces, Grey relation analysis is used. The graph plots the Signal to Noise ratio which identifies the optimal process parameters. The work material used for experimental work is aluminium alloy AA 6061.