Effect of the counterpart material on wear characteristics of silicon carbide ceramics

The pin-on-disc dry sliding friction and wear experiments have been made on SiC ceramics in contact with Si3N4, Al2O3, and ZrO2 ceramic balls and WC-Co ball at 5 N load in an ambient environment. Coefficient of friction and specific wear rate were measured, and wear damage mechanisms were identified. The friction coefficient of SiC varied in the range of 0.5-0.65 against Al2O3 ball, between 0.62 and 0.67 against Si3N4, in the range of 0.45-0.54 against ZrO2, and between 0.46-0.59 against WC-Co ball. The SiC materials with fine globular microstructure had lower COF and wear rate than SiC materials with coarser rod-like microstructure. The results showed that with the ZrO2 and WC-Co counterpart the wear rate of SiC decreased while with the Si3N4 ceramic counterpart the wear rate of SiC was about one order of magnitude higher. The main wear mechanism was similar for all studied materials in the form of mechanical wear (micro-fracture) and tribochemical reaction (creation of coherent layers composed mainly of a large amount of oxygen).