Synthese et proprietes thermomecaniques de ceramiques denses composites carbure de bore-carbure de silicium

Abstract

Commercial powders of boron carbide and silicon carbide were mixed and sintered without pressure, using a carbon additive produced by the in situ pyrolysis of a Novolac-type phenol-formaldehyde resin. The densities achieved are between 93% and 99% of the theoretical density; the free carbon content is about 1%. The mechanical properties of the composites B x C-SiC determined at room and high temperatures are discussed and compared with those of pure hot-pressed boron carbide.