Manufacture of transition metal carbide, nitride, and carbonitride whiskers containing two or more transition metals

Abstract

There is disclosed a method of producing whiskers in large volumes and at low cost to be used as reinforcing material. The whiskers are solid solutions between two or more transition metal carbides, nitrides and carbonitrides, (Me.sub.1-X-Y.sub.Me'.sub.X+Y)C.sub.1-Z N.sub.Z, having preferably submicron diameters, where Me' is one or more transition metals other than Me. The whiskers are suitable for use as a reinforcement material in a wide range of materials, including metals, intermetallics, plastics, ceramics and metallic bonded hard material. Transition metal oxides, hydroxides or alkali compounds thereof are mixed with carbon powder. The carbon source is added in an amount to satisfy the stoichiometric requirements of the carbide or nitride. A halogenide salt is used as a volatilization agent for the transition metals and a catalyst such as Ni or Co that is able to dissolve transition metals plus C and/or N. The reactant powders are blended so as to intimately mix them. Finally, the mixed starting material is subjected to nitriding, carbonizing or carbonitriding heat treatments in order to produce the desired whiskers.

Dependencies are inferred from the claim text.