SLIDING WEAR OF SILICON-CARBIDE TITANIUM BORIDE CERAMIC-MATRIX COMPOSITE

The tribological behavior of a SiC-TiB2 ceramic-matrix composite was e valuated using a pin-on-flat contact configuration in reciprocating sl iding. A steady-state friction coefficient of about 0.55 and an averag e specific wear rate of about 2 x 10(-6) mm3.N-1.m-1 were measured. Th e mechanisms of material removal involved failure of the particle-matr ix interface, resulting in particle pullout and chipping of the matrix material. The generated wear debris was often recycled through the co ntact interface, resulting in the production of submicrometer fine par ticles that reattached to the surface and were later removed in flake form. Transitions were observed in the specific wear rate from higher to lower values as sliding progressed. These transitions were accompan ied by transitions in the nominal contact pressure.