Abstract: There is disclosed a method of producing, in large volumes and at low cost, Ta, Nb, Zr and Hf carbide, nitride or carbonitride whiskers, preferably submicron, having excellent reinforcing properties, suitable as reinforcement in a wide range of materials, including metals, intermetallics, plastics, ceramics and metallic bonded hard material. Oxides of Ta, Nb, Zr and Hf or alkali compounds thereof in an amount to satisfy the stoichiometric requirements of the desired carbide or nitride are mixed with the carbon source along with an alkali and/or alkali earth metal halogenide as a volatilization agent for the metal and a catalyst for the whisker growth such as Ni and/or Co. The reactant powders are blended in some typical manner using a high speed blender so as to intimately mix them. Finally, the starting material is subjected to nitriding, carbonizing or carbonitriding heat treatments in order to produce the desired whiskers.

Abstract: The presently claimed invention relates to a method of producing, in large volumes and at low cost, transition metal carbide, nitride or carbonitride whiskers, preferably submicron, having excellent reinforcing properties. These whiskers are suitable for use as a reinforcement in a wide range of materials, including metals, intermetallics, plastics, ceramics and metallic bonded hard material. The basic idea is the use of a carbon source with a volatile part which volatiles at temperatures up to 1000.degree. C. Transition metal oxide or alkali compounds thereof in amounts to satisfy the stoichiometric requirements of the desired carbide or nitride is mixed with the carbon powder along with an alkali metal chloride powder as a volatilization agent for the metal and a catalyst for the whisker growth such as Ni or Co. The reactant powders are blended in some typical manner using a high speed blender so as to intimately mix them.

Abstract: A process for producing silicon carbide whiskers in which a particulate form of carbon is combined with a silicon component, a boron component and seeding component to form a mixture which is then subjected to temperatures above about 1300.degree. C. in a nonoxidizing atmosphere such that carbon reacts with silica to form silicon carbide whiskers. The preferred particulate carbon, silicon component, boron component and seeding component are, respectively, carbon black, fumed silica, boron oxide and cobalt, iron or nickel. The size and shape of the whiskers can be controlled by varying the size of the seeding component and the concentration of the boron component.