Abstract: A method for producing alumina-silicon carbide ceramic powders by in situ production of silicon carbide particles by introducing a pyrolyzable carbon source, preferably a gaseous hydrocarbon, into a reactor containing an alumino-silicate, pyrolyzing the pyrolyzable carbon source to form carbon particles in situ, wherein the carbon particles are capable of reacting with a silicate in the alumino-silicate to form carbide products, and then reacting the silicate and the carbon particles in situ at an effective temperature, preferably at least 1450.degree. C. and more preferably at least 1500.degree. C., for a sufficient time to transform the alumino-silicate and the pyrolyzable carbon source into the composite ceramic powder having alumina (Al.sub.2 O.sub.3) and silicon carbide (SiC) as major phases.

Abstract: A method of producing ceramic composites of Al.sub.2 O.sub.3 reinforced by shaped SiC particles preferably shaped as fine particles (random), platelets, whiskers or fibres by in situ production of SiC particles by heating a mixture of carbon particles of the desired shape with silicates of Al.sub.2 O.sub.3 to a temperature above 1500.degree. C., convert the silicates and carbon to Al.sub.2 O.sub.3 and SiC to produce in situ SiC particles of the desired shape and provide a ceramic powder that may be densified by techniques such as hot pressing, isostatic pressing or sintering.