PRODUCTION OF GRAPHITE BASE MATERIAL FOR BETA-SILICON CARBIDE MOLDED PRODUCT AND GRAPHITE BASE MATERIAL FOR BETA-SILICON CARBIDE MOLDED PRODUCT AND BETA-SILICON CARBIDE MOLDED PRODUCT

摘要

PROBLEM TO BE SOLVED: To provide a graphite base material of raw material optimal for obtaining substantially 100% SiC molded product by the performance of a CVR method, to provide a method for producing the graphite base material, enabling the efficient production of the graphite base material, and to provide an extremely highly pure SiC molded product capable of being sufficiently applied as a raw material for the field of semiconductors. ;SOLUTION: This method for producing a graphite base material for β-SiC molded products comprises grinding a raw material for the graphite base material, kneading the ground product, molding the kneaded product, calcining the molded product and subsequently graphitizing the calcined product. Therein, the raw material for the graphite base material is thermally treated at a high temperature (≥2,000°C), ground, classified into a fraction having particle diameters of at least 3-100 μm, and subsequently kneaded. Thus, the β-silicon carbide molded product having a bulk density of ≤1.50 Mg/m³, an average pore radius of ≥1.5 μm, a true density of ≤1.8 μm is obtained. The obtained graphite base material is treated by a CVR method to obtain the SiC molded product, which has impurity concentrations (Fe, Al concentrations) comprising a Fe concentration of ≤0.5 ppm and an Al concentration of ≤0.1 ppm and has an ash of ≤10 ppm.;COPYRIGHT: (C)1999,JPO