Optimization of process parameter of FS-welding of aluminum-lithium alloy (AA8090) by using desirability analysis

This study explores the potential of Friction Stir Welding (FSW) for Aluminum Lithium (AA8090) Alloys, emphasizing the crucial role of experimental investigations in optimizing the FSW process. Using a vertical machine center (VMC) with a customized fixture and tool for FSW, factors like Rotational speed (RS), Tilt angle (TA), and Welding Speed (WS) are considered to enhance ultimate tensile strength (UTS) and % elongation (EL). A regression model based on Response Surface Methodology’s Central Composite Design (CCD) is used to analyze UTS and % EL. The effectiveness of welded joints is comparable to the parent metal, with optimal UTS and EL achieved at 1428 rpm rotational speed, 36.4 mm/min welding speed, and 1.5° tilt angle. While significant interaction effects are observed in UTS, none are noted in EL. FSW joint performance is evaluated through microstructural analysis, microhardness distribution and fractography analysis.