Wear characteristics of as-cast ZA-27/graphite particulate composites

Abstract

This paper reports a study on the wear properties of cast ZA-27 alloy matrix composites. The unreinforced matrix, and the composites containing 1%, 3% and 5% by weight, of graphite particles, were tested. Sliding wear tests were conducted using wear loads of 3, 4 and 5 kg f (29.43, 39.24 and 49.05 N, respectively) and wear rotational test speeds of 200, 260 and 320 rpm (i.e. tangential sliding speeds of 1.25, 1.63 and 2.00 m s-1, respectively), using a pin-on-disc sliding wear testing apparatus under dry (unlubricated) conditions. Results of the wear tests revealed that the wear rate decreased with an increase in the graphite content. The wear resistance improved most significantly at low graphite contents. The wear rate was also found to increase with an increase in wear load, and decrease with an increase in wear speed. An attempt is made in this paper to explain these phenomena in terms of the smearing process of graphite during sliding. Copyright © 1996 Elsevier Science Ltd.