Abstract:For aluminum alloy, friction stir welding (FSW) is the most suitable welding technology, but if the FSW tool used or the FSW parameters selected are unsuitable, various defects will occurred in weld joint, which damages its quality. The three easily adjustable factors, ie. tool rotary speed (A), tool traverse speed (B), and axial force (C), were selected as controllable factors. Considering the interactions between controllable factors, various experiments were performed according to the orthogonal table L27(313). The tensile strength was selected as the evaluation index. The optimized process parameter combination was obtained as A3B2C2, ie. A at the third level, B at the second level, and C at the second level, with the range analysis and interaction utility analysis. The significance of the controllable factors on the evaluation index was obtained with variance analysis. The results were confirmed by further experiments.