Tribological properties of Al-Cu/SiCp metal-matrix composites fabricated using the rheocasting technique

Abstract

This paper reports the outcome of an investigation into the tribological (friction and wear) properties of a group of aluminium alloy-based SiC particulate reinforced metal-matrix composites (MMCs). These MMCs (Al-4.5Cu/SiCp) were fabricated using the rheocasting process. The amount of SiC particulates was kept at 13 vol%. A series of unlubricated pin-on-disk tests was carried out to examine the tribological characteristics of this group of MMCs. In general, at a sliding speed of 1 m/s and normal loads ranging from 30 to 70 N, the rate of wear increased with increasing applied normal load. More specifically, the rheocast samples exhibited a better wear resistance at higher loads when compared to MMCs having the same composition but fabricated using the powder metallurgy route incorporating mechanical alloying. The wear resistance of rheocast composites has also been found to be comparable to commercially available composites of similar composition, suggesting that the rheocasting process used in the present study can produce quality composites for tribological applications.