Floating catalyst chemical vapor infiltration of nanofilamentous carbon reinforced carbon/carbon composites-Tribological behavior and wear mechanism

Nanofilamentous carbon (NFC) reinforced carbon/carbon composites were produced by floating catalyst chemical vapor infiltration. The study on the tribological properties showed that, the average friction coefficient and wear rate decreased firstly before an increase with the rising catalyst content from 0 to 1.2 wt% and treatment temperature from 2100 to 2500 °C. The composites exhibited low wear rate and stable friction coefficient with the catalyst at 0.5-0.8 wt% and treatment of 2300 °C, due to the high physical and mechanical properties. The wear increase for 1.2 wt% catalyst and treatment of 2500 °C arose from the isotropic pyrocarbon and limited NFC growth and the strength degradation, respectively. High braking pressure and energy resulted in wear aggravation by the rapid ejection of wear debris and high oxidation.