Chiang Mai Journal of Science

     Friction stir welding (FSW) of aluminium alloy AA1100 is investigated in this work. The process parameters considered in the work includes; tool tilt angle, tool pin geometry, tool rotational speed and welding speed. The tensile strength, welding temperature and hardness are considered as the responses and selection of optimum welding process parameters for maximizing tensile strength, hardness and minimization of the welding temperature are demonstrated using Taguchi technique and Response surface methodology. Four levels for the welding process parameters are selected and Taguchi L16 orthogonal array is used to perform 16 experiments as designed by the design of experiments software. Aluminium alloys of AA1100 of thickness 2mm are chosen for this experimental work. The specially designed tool which is made up of high tool steel material is used in this Friction Stir Welding (FSW) process. Tool pins of various shapes are considered in this study. ANOVA analysis is carried out for every response and the S/N ratio for the strength, hardness and welding temperature are determined and the main effects plots for signal to noise ratio are plotted and discussed. The microstructure of the grain size infl uences the tensile strength of the weld joint. It is observed that the tool tilt angle provides very less infl uence in the determination of the tensile strength during FSW of AA1100 aluminium alloy. It is observed that by increasing the tool tilt angle, tool penetration into the specimen will increase and as a result it leads to an increase in the welding temperature.