| 摘要 |
PROBLEM TO BE SOLVED: To readily and efficiently produce a highα-type silicon nitride powder by adding and mixing a metal silicon fine powder to a metal silicon powder and nitriding the mixture in a specified temp. range in a nonoxidative gas atmosphere containing nitrogen. SOLUTION: A metal silicon fine powder having <20μm particle size is added and mixed by 5 to 35wt.% to a metal silicone powder having 20 to 100μm particle size. The mixture as the source material is nitrided at 1150 to 1400 deg.C temp. range for 1 to 100 hours in a nonoxidative gas atmosphere containing nitrogen. As for the nitriding gas, nitrogen or ammonia or a mixture of these are preferably used. If necessary, hydrogen, argon, helium and the like may be added to control the reaction. Thereby, a highα-type silicon nitride powder having >=90%α-type component can be easily and efficiently produced.
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