Friction and wear characteristics of PEEK and its composite under water lubrication

Abstract

The friction and wear performance of pure polyetheretherketone (PEEK) and 30% carbon fiber-reinforced PEEK composite were comparatively evaluated under dry sliding and water drops lubrication. The sliding experiments were carried out on a pin-on-disc tribometer. The contact configuration used was a polymer pin on a rotating AISI D2 steel disc. Wear tests were carried out at room temperature under 50, 100, 150, and 200N loads and at 0.40m/s sliding speed. The results show that the coefficient of friction for pure PEEK increases with the increase in load value, while the coefficient of friction for 30% carbon fiber-reinforced PEEK is not significantly influenced by the increase in load. In addition, the coefficient of friction for PEEK+30%CF is lower than that of pure PEEK at both dry sliding and water-lubricated conditions. Moreover, for the range of load and speed of this study, the coefficient of friction using water lubricant registered lower values than that of the dry condition. Finally, the specific wear rates for pure PEEK and PEEK+30%CF composite under water-lubricated conditions were in the order of 10(-15) m(2)/N, while under dry sliding conditions this value is in the order of 10(-14) m(2)/N.