Frictional performance of silicon carbide under different lubrication conditions

The frictional performance of materials used in face seals is critical to the sealing performance. Silicon carbide is commonly used in hard rings because of its abrasion resistance, corrosion resistance, and thermal shock resistance. In this study, the frictional performance of silicon carbide, including graphite-added silicon carbide, under water and lubrication-absent conditions was studied by using a Falex-1506 tribotester and different working parameters. In addition, the morphology of the worn surfaces was observed using scanning electron microscopy and the damage was characterized to understand the tribological behavior of different silicon carbides. The results suggest that the friction coefficients decrease with increasing pressure under water lubrication conditions because of the water within the holes on the surface of the materials. The percentage of water lubrication increases, whereas the percentage of solid friction decreases when the pressure increases. Under dry contact conditions, the friction coefficients change negligibly with increasing pressure and graphite-added silicon carbide shows better frictional performance.