Various TiN-TiB2-Ti5Si3 composites have been synthesized via spark plasma sintering of Ti, BN and Si3N 4. The reaction process anlaysis indicates that Ti5Si 3 forms earlier than TiB2. The reaction heat as well as the Joule heat may prompt the melting of Ti5Si3, making it infiltrate into TiN and TiB2. Thus, the composites can be further densified with the in-situ addition of Ti5Si3. For TiN-TiB2-Ti5Si3 composites, the maximum fracture toughness was 4.5± 0.3 MPa·m1/2, and maximum flexural strength was 601.1± 28.5 MPa, which were both quite higher than those of TiN-TiB2 composites. The related toughening and strengthening mechanisms were proposed from microstructural analysis.
ASJC Scopus subject areas
- 化学 (全般)