Elucidating the Effect of Friction Stir Welding Variables on HDPE Sheets Using Grey Integrated with Fuzzy: Experimental Investigation and Parametric Optimization

The present work aims to assess the best friction stir welding (FSW) parameter for HDPE sheet weld joints. In this context, tool rotational speed, tool transverse speed, and tool tilt angle have been considered as control parameters. The experiments have been planned according to Taguchi’s L16. The process outcomes were evaluated in terms of tensile strength and elongation. Analysis of variance methodology has been implemented to evaluate the most significant control parameter regarding process outcomes. These outcome values have been used to optimize the FSW control variables using the concept of Grey relational analysis. In addition, the integration of the Grey concept and fuzzy system has also been explored to analyze the optimum welding combination. When compared, it was found that both optimization routes yielded identical outcomes in terms of parametric optimization. The favorable welding conditions were obtained with a tool rotation speed of 1070 rpm, a tool traverse speed of 20 mm/min, and a tool tilt angle of 2° for maximum output response, whereas the tool rotation speed was obtained as the most influential control parameter.