T. Waldek Zerda
Reactive sintering of diamond-SiC nanocomposites is possible by thorough mixing of diamond, silicon nanosize powders, and carbon nanotubes or by ball milling mixtures of diamond and silicon powders. Properties of nanocomposites were characterized by scanning electron microscopy, XPS, Raman scattering and x-ray diffraction. Diamond-SiC nanocomposites have remarkably high fracture toughness and are significantly harder than the sintered pure nanocrystalline diamond compacts. X-ray lines broadening was explained in terms of detects and stacking faults and average sizes of diamond and silicon carbide crystals. Results were compared with those obtained for pure diamond and silicon carbide nanocrystals after high pressure, high temperature treatment. Sintering of SiC nanowires from carbon nanotubes will be also discussed.