Silicon nitride containing various compositions of as-received TiC and TiN-coated TiC, were hot pressed at 1800°C for 1 h in a nitrogen atmosphere. In TiN-coated TiC/Si3N4 composites, TiC reacted first with the TiN coating to form a titanium carbonitride interlayer at 1450°C, which essentially reduced further reactions between TiC and Si3N4 and enhanced densification. TiN-coated TiC/Si3N4 composites exhibited better densification, hardness, flexural strength and fracture toughness than those of as-received TiC/Si3N4. The toughening mechanisms for as-received TiC/Si3N4 and TiN-coated TiC/Si3N4 composite were attributed to crack deflection, load transfer and crack impedence by the compressive thermal residual stress.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering