ULTRAHARD COMPOSITES

摘要

The present invention concerns an ultrahard composite material comprising ultrahard particles dispersed in a nano-grain sized matrix material, wherein the average grain size of the matrix material, or at least one component of the matrix material, is within 30nm of the Hall-Petch departure grain size for the matrix material or at least one component thereof. The ultrahard particles in the composite are cubic boron nitride and / or diamond, and the matrix materials are of a controlled and chosen phase and nano-grain size. Ultrahard composites with cubic boron nitride and diamond in nano- matrices of titanium nitride, zirconia, alumina, silica and chromium nitride are provided.