Effect of process parameters on thermal history and mechanical properties of friction stir welds

In this paper, effect of process parameters such as tool rotation and weld speed on temperature distribution and mechanical properties of aluminum alloy AA2014 joined by friction stir welding was investigated. A three dimensional transient thermal model using finite element code ANSYS was developed and experimentally validated to quantify the thermal history. To systematically study the influence of input parameters, nine experiments based on full factorial design were performed. Samples were prepared and welded by varying input parameters such as tool rotation and weld speed. The analysis of variance (ANOVA) was employed to investigate the effect of input parameters on thermal history and mechanical properties of weld. Temperature measurements and analysis of variance (ANOVA) indicated that the temperature under the tool was strongly dependent on the tool rotation speed than the weld speed. The results also indicated that weld speed could be the main input parameter that had the highest statistical influence on mechanical properties.