Friction Characteristics of Carbon Versus Silicon Carbide under Stepwise Loading Conditions

Abstract

Friction characteristics of face-seal materials have been studied using a thrust-washer (face-loaded) contact fixture, which includes a rotating carbon ring against a stationary, mating silicon carbide (SiC) ring. A computerized test machine was used to conduct the friction measurements. Two types of carbon ring materials (antimonyfilled and resin-impregnated) were used to rub against a common SiC. Two different media (tap water and light oil) were selected as sealing fluids. The influence of load and speed on the friction and temperature of the test seal rings was examined and compared among the carbon materials and lubrication media. The test results show that, in oil-lubricated runs, coefficients of friction are larger than their counterparts obtained under the same speed and material combination but in water lubrication. The bulk temperature in oillubricated experiments is much higher than in water-lubricated tests. When the sliding speed is increased, the coefficient of friction is usually decreased, but the bulk temperature is generally increased.