METHOD OF PREPARING POWDER-LIKE COMPLEX CERAMIC MATERIALS BASED ON REFRACTORY ALLOYS Russian patent published in 2004 - IPC

FIELD: refractory materials. SUBSTANCE: invention relates to chemical and electrochemical and ceramics industries for use in manufacture of cutting tools, polishing compositions, chemically resistant and conducting coatings. 480 g of refractory metal oxide, e.g. titanium oxide with submicron particle size, are mixed with 72 g of nonmetal, e.g. carbon black. 530 g (10% stoichiometric excess) of reducing metal, in particular calcium in the form of balls less than 500 mcm in diameter are then added. Resulting mixture is stirred and placed into mold or tubular reactor, after which reaction in argon flow is initialized. When self-propagating reaction is ended, product is cooled under argon and CaO formed is dissolved in HCl or AcOH. Reaction temperature can be regulated by cooling reactor walls. Submicron titanium carbide powder obtained has average particle size 0.7 mcm and contains 0.6% oxygen. Refractory metal oxide can be represented by HfO₂,ZrO₂ or TiO₂. Nonmetal can be used in pure state or in the form of calcium-containing compound, for instance CaC₂,Ca₃N₂ or CaCN₂. Reaction temperature can be controlled by adding fusible salt, e.g. NaCl, to reaction mixture. EFFECT: enabled preparation of carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, mixed carbides or nitrides. 11 cl, 7 dg, 7 ex