Friction and Wear Properties of Copper-Based Sintered Materials Containing Various Intermetallic Compounds

The friction and wear characteristics of copper-based sintered materials containing various intermetallic compounds were investigated under dry sliding conditions over a speed range of 1-4m/s, and compared with those of the Cu-A12O3 sintered compact. Four different kinds of intermetallics; CuAI, Cu2AI, Co2Ti and Ni3Al, were used to take account of both hardness and softening temperature. The fraction of added hard powder with a particle size of 105-150 μm was 16 vol% to copper powder, The addition of the intermetallic powder with relatively high softening temperature such as Co2Ti and Ni3Al was quite effective, irrespective of the hardness, indicating that the softening temperature was the crucial factor for the improvement of the friction and wear behaviours. The Cu-Ni3A1 sintered material exhibited the most excellent tribological performance. The superiority of Ni3Al as an anti-wear additive may be caused by the formation of the softer diffusion layer which envelops the harder core of Ni3A1 particles, besides the high softening temperature and the positive temperature dependence of hardness. Al2O3 powder was further crushed to several fragments during sliding, because it is devoid of ductility. This results in an inferior wear resistance for the Cu-Al2O3 sintered material.