Mechanical and Dry Sliding Wear Behaviour of Al-6061/Al2O3/Mica Hybrid Composites Fabricated via Stir Casting

The present study focuses on the synthesis and performance evaluation of Al-6061-based hybrid metal matrix composites reinforced with alumina (Al?O?) and mica particulates. Four composite formulations were fabricated through the stir-casting process by varying Al?O? content (2, 4, 6 and 8 wt.%) while maintaining a fixed 4 wt.% mica reinforcement. Mechanical behaviour was examined through Vickers microhardness and tensile tests, whereas dry sliding wear performance was assessed on a Pin-on-Disc tribometer under varying load, sliding speed and sliding distance conditions. Results revealed a substantial enhancement in hardness and tensile strength for all composites compared with the unreinforced matrix. The highest mechanical performance was achieved in Composite-4 (8 wt.% Al?O? + 4 wt.% mica), primarily due to improved interfacial bonding and effective load transfer. Wear and coefficient of friction increased with applied load across all composites; however, reinforcement addition markedly reduced material loss relative to the base alloy. Composite-4 exhibited the lowest wear rate, followed closely by Composite-3, indicating superior tribolayer stability and resistance to abrasive and adhesive wear. Overall, the findings demonstrate that the incorporation of Al?O? and mica synergistically enhances both mechanical integrity and surface durability of Al-6061, making these hybrid composites suitable for high-strength and wear-resistant engineering applications.