Optimizing Friction Stir Welding of Al 6061 Alloy Using Statistical Analysis

Abstract

In this study, a three-way factorial design is used to optimize the friction stir welding (FSW) process of Al 6061 alloy. Control factors are shoulder diameter, travel speed, and rotation speed of tool, and each factor has three levels. Tensile strength tests are also carried out to measure the mechanical properties under various FSW conditions. In this work, travel speed, shoulder diameter, and tool speed are shown to individually be meaningful factors in the tensile strength of the alloy, but interactions among the weld factors are not detected. The result of the study is that the optimum process condition for maximum tensile strength is estimated to be A₃B₃C₃. In addition, the presumed range of tensile strength under the optimal conditions is estimated to be 257±23 (Mpa) with 95% reliability.