Abstract
W2C nano-particle reinforced Si3N4 matrix composite was fabricated by sintering tungsten solution-infiltrated porous Si3N4, and the microstructures and tribological behaviors of W2C-Si3N4 and sulphurized W2C-Si3N4 composites were studied. By incorporating the W2C nano-particles into the grain boundary phases of Si3N4, not only the mechanical properties, but also the wear behaviors were improved. After sulphurization, the nano-merter sized WS2 particles were observed form the surface of W2C-Si3N4 composite. The average friction coefficient and specific wear rate of the sulphurized W2C-Si3N4 composite were ~ 0.41, 0.56 ×10-9mm2/N, respectively, under dry condition, ~ 34%, 47% lower than those for the Si3N4. The formation of the solid lubricant WS2 on the surface of the W2C- Si3N4 composite lowered the both friction coefficient and specific wear rate, and exhibited the self-lubricant behavior during the sliding wear.
