Study of Mechanical Properties and Tribological Behaviour of Al-SiC Composite Fabricated by Powder Metallurgy in a Nigerian University Laboratory

This study examines the mechanical properties and tribological behaviour of aluminium-silicon carbide (Al-SiC) composites fabricated using the powder metallurgy route at a university laboratory in Zaria, Kaduna State, North West Nigeria. Powder metallurgy offers advantages over casting for producing fine, uniformly distributed reinforcement particle composites, and developing this processing capability at Nigerian universities supports the long-term goal of indigenous advanced material production. Commercial aluminium powder and SiC particles (average size 20 micrometres) are blended at SiC volume fractions of 5, 10, 15, and 20 percent, cold-pressed at 300 MPa, and sintered at 550 degrees Celsius for 2 hours under argon atmosphere. Sintered specimens are characterised for relative density, hardness, tensile strength, and microstructural distribution of SiC particles by SEM. Wear testing is conducted on a pin-on-disc tribometer at loads of 10, 20, and 30 N and sliding speed of 1.5 m/s under dry conditions. Results show that hardness and wear resistance increase monotonically with SiC content up to 15 percent, beyond which particle clustering reduces the improvement rate. Tensile strength peaks at 10 percent SiC. Specific wear rate decreases by 65 percent at 15 percent SiC compared to monolithic aluminium. The study demonstrates the feasibility of powder metallurgy composite fabrication in a Nigerian university laboratory setting. Keywords: aluminium-SiC composite, powder metallurgy, tribological behaviour, mechanical properties, Kaduna State.