Wear Behavior of PAN- and Pitch-Based Carbon Fiber Reinforced Aluminum Alloy Composites under Dry Sliding Condition

The effects of carbon fiber-reinforcement on the wear behavior of aluminum alloy under a dry sliding conditions have been investigated. Two kinds of carbon fibers, PAN-based and pitch-based short carbon fibers, were used as the reinforcements. The composites were fabricated by squeeze casting, and wear testing was carried out using the pin-on-disk method. The wear loss of the alloy and counterpart decreased due to the fiber-reinforcement. The change in the coefficient of friction during the wear test and the scatter in the roughness of the worn surface also decreased by the reinforcement. Examination of the worn surfaces and temperature change of the specimens during the wear revealed that these results were mainly attributed to the crumbled fibers forming a solid lubricant film on the worn surfaces thus preventing seizure of the matrix with the counterpart. Under a high load and sliding speed, the wear loss of the pitch-based fiber composite was lower than that of the PAN-based fiber one. The examination described above revealed that the improvement in the wear and seizure resistance was mainly attributed to the higher thermal conductivity of the pitch-based fiber composite.