Ni 3Al matrix high temperature self-lubricating composites

Abstract

A Ni 3Al matrix high temperature self-lubricating composite Ni 3Al–BaF 2–CaF 2–Ag–Cr was fabricated by the powder metallurgy technique, and tribological behavior at a wide temperature range from room temperature to 800 °C was investigated. The results indicated that the composite exhibited low friction coefficients (0.30–0.36) and wear rates (0.65–2.45×10 −4 mm 3 N −1 m −1). It was found that the low friction coefficient was attributed to the synergistic effects of Ag, fluorides and chromates formed in the tribo-chemical reaction at high temperatures. The low wear rate of the composite was due to the high strength and the excellent lubricating properties.