Friction characteristics of carbon versus silicon carbide under stepwise loading conditions

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 (antimony-filled 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 fraction 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 bat in water lubrication. The bulk temperature in oil lubricated experiments is much higher than in water-lubricated tests. When the sliding speed is increased, the coefficient of friction is usually decreased bat the bulk temperature is generally increased.