Processing and characteristics of TiB2 toughened
B-Ti-C composites
B-Ti-C composites
(School of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, China)
Harbin Institute of Technology, Harbin 150001, China)
Abstract: B-Ti-C composites toughened by TiB2 particles were produced by reaction sintering of B4C, TiC and TiB2 powders. Microstructure and mechanical properties of the composites were studied. A notable improvement on flexure strength and fracture toughness were achieved in B4C composites containing 10%TiB2 and 20%-30%TiC(volume fraction). The highest flexure strength and fracture toughness, 425MPa and 8.2MPa·m1/2, respectively, resulted for B4C-10%TiB2-30%TiC composite, are much higher than those for monolithic B4C. The main toughening mechanism is microcrack toughening and crack deflection toughening.
Key words: B-Ti-C composites; microstructure; mechanical properties; toughening mechanism