Study On The Friction And Wear Properties Of Copper-Matrix Anti-friction Composites Under Different Temperatures

Self-lubricating materials show unique advantages especially in lubricating conditions without or with a little oil. As one of the most important metal matrix anti-friction composite, copper matrix anti-friction composite has received a variety of applications because of their excellent tribological properties. However, the related previous work mainly was taken at room temperature, the friction and wear of this composite at different temperatures are rarely reported. Therefore, this thesis will study wear behavior and mechanism of copper matrix anti-friction composites in different service conditions systematically, and analyze the wear and anti-friction process of the composites theoretically in order to provide a theoretical fundamental and technical supports for the development of new type high performance copper anti-friction composites.By the testing of the wear and friction and using of OM (optical microscope),XRD (X-ray diffraction) and Ferrography etc, this thesis analyzed the microstructures, compositions of the wear particles and worn surfaces of the composites, and discussed the wear behaviors and mechanisms from room temperature to 500℃in detail. During the wear process, solid lubricating particles were pressed and moved to surface, and then gradually deformed into continuous thin solid lubricating film. It is benefit for increasing the covering percentage of the lubricating film and the strengthening of the anti-friction composite to improve the anti-friction and wear of the composites. Under the testing conditions, the composites showed good anti-friction: low coefficient of friction and low wear rate. The wear of the composites increased and anti-friction became worse with the increase of the testing temperature. The results showed that the main wear mechanisms of copper matrix anti-friction composites under higher temperatures were the cracking, peeling off of lubricating film, the heavy plastic deformation occurred in the subsurface area, and accompanied with oxidation wear.This thesis investigated the wear behaviors of the copper-matrix anti-friction composites from room temperature to 500℃. It is of great significances in theory and practice to develop the new type of copper-matrix anti-friction composites and to enrich the tribological research.