Effect of Process Parameters on Mechanical Properties of Friction Stir Welded AA6061-T6 Alloy

Abstract

Friction Stir Welding (FSW) is a solid-state joining process frequently employed to join aluminum alloys because it offers defect-free joints with excellent mechanical properties. This work examines the influence of welding parameters on the mechanical properties of AA6061-T6 aluminum alloy welds. A Taguchi L16 orthogonal array was employed to study the effect of rotational speed, traverse speed, axial force, and tool tilt angle. A constant geometry H13 steel tool was used to perform experiments, and tensile strength, microhardness, and percentage elongation were measured. The outcomes demonstrate that all the process parameters have a profound influence on the weld quality, but rotational speed is found to be the most influential, followed by axial force, traverse speed, and tool tilt angle as per ANOVA analysis. A nonlinear trend of mechanical properties was observed as a result of interaction effects between heat input, material flow, and deformation. The best combination of process parameters (1400 rpm, 60 mm/min, 6 kN, and 1°) produced the highest tensile strength (235 MPa), hardness (83 HV), and elongation (13%). These improved mechanical properties are due to better mixing and dynamic recrystallization in the stir zone. The research shows that the choice of process parameters is essential to produce high-quality friction stir-welded joints in AA6061-T6 aluminum alloy.