High-speed tribological properties of some Al/SiCp composites: I. Frictional and wear-rate characteristics

The friction and wear behaviour of four Al/SiCp composites has been investi gated over a wide range of sliding conditions by the use of a specially ada pted high-speed tester of the pin-on-disk configuration. Two of the composi tes tested were fabricated in-house by a powder metallurgy route incorporat ing mechanical alloying; two commercially sourced composites were also test ed far comparison. Generally, wear rate increased with increasing load, but it varied in a rather complex manner with speed depending on which regime the sliding condition fell into. Three regimes of tribological behaviour, d emarcated by sliding speed, were observed for these composites. In Regime I , lower rates of wear are observed while in Regime II, catastrophic failure s occur when a certain critical load is exceeded, resulting in the rapid ad hesion of a large amount of specimen material to the counterface: it is no longer possible to continue with the test when this happens. In Regime III, extensive melting of the composites takes place, and under such a sliding condition, the size of reinforcement particles appears to have an important influence on the rate of wear of these composites. (C) 1999 Elsevier Scien ce Ltd. All rights reserved.