Tribological Property of Ni3Al Matrix Composites with Addition of BaMoO4

The Ni3Al matrix composites with addition of 10, 15, and 20 wt% BaMoO4 were fabricated by powder metallurgy technique, and the tribological behaviors were studied from room temperature to 800 A degrees C. It was found that BaAl2O4 formed during the fabrication process. The Ni3Al composites showed poor tribological property below 400 A degrees C, with high friction coefficients (above 0.6) and wear rates (above 10(-4) mm(3)/Nm). However, the composites exhibited excellent self-lubricating and anti-wear properties at higher temperatures, and the composite with addition of 15 wt% BaMoO4 had the lowest wear rate (1.10 x 10(-5) mm(3)/Nm) and friction coefficient (0.26). In addition, the results also indicated that BaAl2O4 for the Ni3Al composites did not exhibit lubricating property from room temperature to 800 A degrees C.