Influences of carbon fabric/epoxy composites fabrication process on its friction and wear properties

In this paper, several composites of epoxy reinforced with carbon fabric were fabricated with different processes. Tribological properties of the composites which paired with 45 carbon steel under unlubricated ring-on-ring face contact sliding condition were carried out on a friction and wear tester which was typed by MPX-2000. A scanning electron microscope (SEM) equipped with an energy-dispersive X-ray analyzer (EDS) attachment was used to analyze the worn surfaces of carbon fabric/epoxy (CF/EP) composites and counterparts after experiments. The results showed that composite fabricated with semidry process tended to exhibit a uniform mu-t behavior among specimens in the same group as well as on different layers of each specimen as compared with those fabricated with wet process. The mu-t behavior of the composite characterized by two steady stages when the cohesive content was less than 40 vol.%. The first steady-state mu decreased with the lubricant filler contents increasing and the second steady-state mu tended to be close (0.35-0.4). However, mu-t behavior remained smoothly when the cohesive content was more than 40 vol.%. Lower steady-state mu could be achieved by the composite fabricated by epoxy resin with lower softening point and modified by MoS2 and graphite. But the wear rate increased correspondingly. SEM and EDS results indicated that lubricant component in the wear debris evenly distributed on the worn surface which underwent fatigue wear played an important part in reducing the CF/EP composite friction coefficient. (C) 2008 Elsevier B.V. All rights reserved.