beta-CRISTOBALITE, MANUFACTURING METHOD THEREFOR AND NON- OXIDE BASED CERAMIC MATERIAL

摘要

PROBLEM TO BE SOLVED: To produce β-cristobalite and to provide its manufacturing method, by which stable β-critbalite is easily obtained without phase transfer, and to obtain a non-oxide based ceramic material whose oxidative degradation is suppressed and having excellent durability. SOLUTION: The β-cristobalite is obtained by mixing an alkoxide of silicon, silicon carbite or silicon nitride with a solution prepared by dissolving an aluminum halide and a calcium halide in a solvent, filtering solid substance not dissolved in the solvent and firing the same. The non-oxide based ceramic material is obtained by forming a coating layer based on a precursor of the β-cristobalite on the surface of a non-sintered compact (powder) or a sintered compact (molding) of the non-oxide based ceramic. By sintering it at 800-1,800 deg.C, the precursor of the β-cristobalite is converted to the β-cristobalite.