Beta-silicon carbide whiskers of superior uniformity can be formed, either singly or in-situ in a matrix, by heating a source for silicon with a source of carbon (greater than 0 percent but less than or equal to about 60 percent of stoichiometric, with respect to the silicon source) in the presence of a titanium-containing catalyst, such as titanocene dichloride. Advantageously, the titanium catalyst can be applied by drying a solution of the titanium catalyst on the carbon and silicon sources. The titanium, carbon and silicon sources are then heated together, preferably to between about 1800.degree. C. and about 1850.degree. C., resulting in a product containing high quality beta-silicon carbide whiskers. The silicon source can be silicon nitride powder, which can either be substantially converted to free-flowing whiskers, or in the alternative, the silicon nitride powder, carbon source and titanium catalyst can be formed into a conventional ceramic matrix prior to conversion to beta-silicon carbide whiskers, so the whiskers formed therein will serve as a reinforcement for the ceramic matrix.