MICROSTRUCTURE AND MECHANICAL PROPERTIES OF TiB_2-B_4C CERAMIC COMPOSITES

摘要

The microstructure and mechanical properties of TiB₂ /B₄C composites have been investi-gated.It was found that both the strength and hardness for TiB₂ greatly increase with the ad-dition of 20 to 30 wt-% B₄C,and the fracture toughness K_IC value remaines on the originalhigh level.The flexure strength,Vicker’s hardness and fracture toughness are 782 MPa,26.2GPa and 7.2 MPam1/2,respectively,for the TiB₂-30 wt-% B₄C composite,compared to450 MPa,21 GPa and 7.0 MPam1/2 for monolithic TiB₂.The toughening and strengtheningmechanisms,have also been discussed.