Structure and tribological property with electric current of Mo₂C modified C/C-Cu composites

Mo₂C coating was fabricated throughout the low-density carbon/carbon (C/C) preform from inside by a molten salt method, and then C/C-Cu composite was obtained by pressureless infiltration. The structure and tribological property with electric current of C/C-Cu composite were studied. The results show that molten Cu infiltrates into the Mo₂C-modified C/C preform spontaneously and retains interpenetrating network structure with the C/C preform. The Mo₂C coating presents good interfacial bonding with Cu and PyC, and pyrolytic carbon(PyC) near the Mo₂C coating presents an order degree improvement as a result of catalytic and stress graphitization in process of generating Mo₂C. With the increase of load, the friction coefficient of C/C-Cu composite decreases, the volume wear rate increases, while the mass loss of counter part decreases gradually. The worn surface under higher load is coated by a more continuous friction film, while roughness of the worn film increases due to adhesion wear. The material experiences oxidation wear during the wear process, and the content of oxygen on wear surface increases with the increase of load.