Friction and wear properties of carbon/carbon composites with different martix carbon

The quasi-3D C/C composites with rough laminar (RL) and smooth laminar(SL) pytolytic carbon were fabricated by needled felt through CVI and impregnation with liquid pitch and resin, and their friction and wear properties under braking pressure of 0.6MPa and worn mechanism were studied. The results show that C/C composites by resin impregnation after CVD with RL have the most stable friction properties and appropriate friction coefficient and low oxidation loss, because the friction surfaces have relatively thick and uniform lubricant friction film and the wear mechanisms are the falling off of part friction film and oxidation wear loss and relatively slight abrasion wear; C/C composites by resin or pitch impregnation after CVD with SL have unstable friction and wear properties and higher wear loss owing to the thin and discontinuous friction film, and the wear mechanisms are also the falling off of part friction film and abrasion wear and larger oxidation wear loss. The higher the density, the more stable the braking curve, and the higher the friction coefficient and the lower the wear rates. Without the protection of pyrolytic carbon, C/C composites by pitch impregnation only have the highest dimension wear rates due to the largely fracture of fibers and the wear mechanism are mainly abrasion wear and oxidation wear.