Impact of friction stir welding parameters and Al2TiO5 reinforcement on the mechanical, wear, and corrosion performance of dissimilar welded aluminium composite joints

Abstract

This study investigates the impact of friction stir welding (FSW) parameters on dissimilar AA5052-Al2TiO5/AA6061-Al2TiO5 composite joints. Tool rotational speed (TRS), feed rate, and aluminum titanate (Al2TiO5) content are varied, and their influence on microstructure, mechanical properties, wear resistance, and corrosion behavior is assessed. Joints fabricated with 1200 rpm TRS, 40 mm/min feed rate, and 2 wt% Al2TiO5 exhibit the highest tensile strength (170.11 MPa) due to grain refinement in the stir zone (SZ). Joints with 3 wt% Al2TiO5 have near-base composite hardness (86.12 HV) and exhibit distinct microstructures across different zones. Samples with superior mechanical properties display finer grains in the SZ, while other zones exhibit elongated grains. The sample reinforced with 3 wt% Al2TiO5 (W9) demonstrates enhanced wear resistance attributed to its high hardness. Additionally, the sample fabricated with 1200 rpm TRS, 40 mm/min feed rate, and 2 wt% Al2TiO5 (W15) displays the lowest corrosion rate (0.44 mpy) due to its fine structure. Fracture analysis reveals different failure mechanisms in tensile and wear testing.