Integrated durability behaviour of friction stir welded AA2060 Al–Li joints: wear, corrosion, and UVaFSW benchmarking

Abstract AA2060 aluminium–lithium alloys are attractive for aerospace structures because of their high specific strength and damage tolerance; however, their friction stir welded (FSW) joints may experience mechanical loading, sliding wear, and corrosive exposure during service. Previous studies have largely examined these responses separately, leaving the integrated durability of AA2060 joints insufficiently understood. This study evaluates the mechanical, tribological, and corrosion performance of AA2060-T8E30 joints produced using a Taguchi L9 FSW matrix. Tensile testing, wear analysis, electrochemical assessment, microscopy, and CRITIC–TOPSIS with GRA validation were used to identify a balanced processing condition. The optimum conventional condition, 1200 rpm, 3 mm s −1 , and 6 kN, achieved 383.9 MPa tensile strength, 7.2% elongation, the lowest specific wear rate, and favourable corrosion resistance. Mechanical and wear behaviour were governed mainly by weld consolidation and near-surface stability, whereas corrosion was more strongly influenced by local electrochemical heterogeneity. Regional SEM observations identified the TMAZ as the most corrosion-susceptible region, followed by the SZ and HAZ. Benchmark ultrasonic vibration–assisted FSW (UVaFSW) trials conducted under matched primary parameters increased UTS by approximately 10–24% and elongation by 75–82%, raising joint efficiency to about 84% while maintaining or modestly improving wear and corrosion resistance. The findings demonstrate that AA2060 joint optimisation should consider structural, tribological, and electrochemical performance simultaneously and confirm the potential of ultrasonic vibration assistance to extend the performance of conventional FSW joints.