The effects of different ceramics size and volume fraction on wear behavior of Al matrix composites (for automobile cam material)

In this study, a number of metal matrix composites were manufactured to determine their tribological properties. AA2124 matrix material, reinforced by SiC, B4C or Al2O3 (of different particle sizes), was used for manufacturing by powder metallurgy. The reinforcing particles were included at 10%, 20% and 30% volume fraction (vf). The matrix and reinforcement powders were compressed at 600 MPa and 615 °C for 30 min in an argon atmosphere. For comparison with the metal matrix composites (MMC), unreinforced AA2124 samples and GGG40 cam material samples (both induction-hardened and untreated) were also prepared for tribological tests. Tribological tests were conducted at 50 N loading with 900 rpm revolution for 30 min under dry conditions. The specific wear rates of the composites reinforced with 10% volume fraction of B4C or SiC are each lower than that of the GGG40 cam material. While the composite having 30% volume fraction of 20 μm SiC gives the best wear performance, the sample with B4C shows the best performance at 10% vf.