| 摘要 |
PROBLEM TO BE SOLVED: To efficiently manufacture a highα-type silicon nitride fine powder having excellent sintering property for a short period of time by a direct nitriding method. SOLUTION: The method of manufacturing the highα-silicon nitride fine powder is performed by making a reaction furnace form a reaction field containing gaseous nitrogen and gaseous ammonia and heated to 1,400-1,700°C, supplying a fine powdery raw material composed of metal silicon powder or a powdery mixture of metal silicon powder and silicon nitride powder and having≤20μm maximum particle diameter while dispersing the raw material with a carrier gas under≥0.2MPa pressure difference between the pressure in a furnace and the carrier gas pressure, retaining in the reaction field for 2-10 sec to nitride the metal silicon. In such a case, the total quantity of Fe, Al, and Ca in the fine powdery raw material is preferably≤50ppm. COPYRIGHT: (C)2004,JPO
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