Friction and wear performance of a NiAl-8 wt% serpentine-2 wt%TiC composite at high temperatures

Abstract

A NiAl matrix composite with addition of 8 wt% serpentine and 2 wt% TiC (NAST) is investigated to identify the improvement of friction and wear performance at high temperatures. The results indicate that compared with pure NiAl alloy, NAST exhibits lower friction coefficients (0.30–0.34) and wear rates (2.25–3.12 × 10–5 mm3 N−1 m−1) over a wide range of temperatures. This is attributed to the formation of self-lubricating films with different percentages of coverage, which are mainly composed of SiO2 and MgO. Besides, raising the test temperature increases the forming ability and completeness of the films to some extent, further ameliorating the friction-reducing and anti-wear properties accordingly. Especially at 500 °C, the specific friction coefficient and wear rate of NAST are about 39.8% and 62.6% less than those of pure NiAl alloy.