Evaluation of the crack resistance of reactive sintered composite materials based on boron carbide

Abstract

The results of studying the crack resistance of reactionsintered B4C--SiC composite materials impregnated with liquid silicon with identification and fracture methods are presented. With an increase in the amount of B4C in the reaction-sintered material, its fragility increases. The crack resistance of the material can be increased from 3,40 to 4,02 MPa·m1/2 (when tested by different methods) by adding to the composite material up to 30 wt. % SiC. The material is destroyed mainly by the intercrystalline (intergranular) mechanism. Ceramics containing more than 90 wt. % B4C, partially destroyed by the transcrystalline mechanism. Ill. 5. Ref. 26. Tab. 2.