Tribology of carbon-containing materials in the carbon dioxide environment at high temperatures

Abstract

The work is devoted to high-temperature tribological testing of carbon-containing materials during friction on 40X13 steel in the temperature range from plus 20 to plus 800 ° C in a carbon dioxide environment. The choice of temperature and test environment is due to the prospects of creating spacecraft drives for operation without lubrication in the atmosphere of Venus. Studies have shown that the friction process in a carbon dioxide environment at a temperature of plus 300 ° C reduces the coefficient of friction, so at a load of 0.5 MPa, the friction coefficient is lower by 67%, and at a temperature of plus 600 ° C the coefficient of friction is lower by 38%. At a load of 1.0 MPa and a temperature of plus 300 ° C, the friction coefficient in a carbon dioxide environment is lower by 55%, and at a temperature of plus 600 ° C the friction coefficient is lower by 45%. In the range of operating temperatures from plus 300 to plus 600 ° C at a speed of 0.16 m/s and a load of 0.5 MPa and 1.0 MPa, the friction coefficient does not exceed the value of 0.3. The friction coefficient decreases with increasing load. At a temperature of plus 500 ° C and a load of 0.5 MPa, the coefficient of friction in a carbon dioxide medium is 1.9 times less than the carbon-carbon composite materials in an air atmosphere, and at a load of 1.0 MPa it is 2.1 times less than a carbon-carbon composite materials in the air atmosphere.