Liquid-phase-sintered SiC shaped bodies with improved fracture toughness and a high electric resistance

摘要

The invention relates to a polycrystalline SiC shaped body, which consists of 96% by weight to 99.5% by weight of hard-material grains having a core/shell structure, 0 to 0.1% by weight free carbon, remainder a partially crystalline binder phase; having the following properties: density at least 99.5% of the theoretical density, dark green coloring of ground sections or polished surfaces through characteristic light absorption in the orange spectral region at 1.8 to 2.2 eV, resistivity of at least 10⁷ ohmcm, and fracture toughness of at least 4.0 MPa.m^{, measured using the bridge method.}