The Research of SiC and Si3N4 Whiskers Reinforced Si3N4 Composites to Improve its Wear and Mechanical Properties

Abstract

To improve the wear and mechanical properties, SiCand Si3N4whiskers reinforced Si3N4composites were sintered by hot press sintering technique at 1800 and 1900°C for 1 h. The Friction and wear behaviors of Si3N4-SiC whisker reinforced Si3N4composites have been studied by using a reciprocating sliding apparatus. The results show that Si3N4-SiC whisker can greatly improve the hardness, fracture toughness and wear resistance of Si3N4. Lower sintering temperature can make both the grain dimension and interface area of the whiskers with the matrix decrease, resulting in relatively uneasy fracture of the whiskers. This uneasy fracture of the whiskers is the main reason for improvement in fracture toughness, and thus, the decrease in wear rate compared with those of the samples sintered at higher temperature and Si3N4material.