| 摘要 |
PURPOSE:Metallic silicon is nitrided, crushed and heat-treated in an inert gas atmosphere to make the iron included in the product as an impurity harmless, thus enabling easy and inexpensive production of silicon nitride powder which is suitable for use as a starting substance of sintered materials. CONSTITUTION:Particles of silicon nitride resulting from nitriding of metallic silicon are crushed by means of a crusher such as an iron ball mill, then roasted by heating in an inert gas atmosphere such as N2, Ar, or He at 700-1,500 deg.C, preferably 1,000-1,200 deg.C to make the iron included in silicon nitride harmless in the form of iron siliconide. Further, they are subjected to crushing with a ball mill which has no danger of contamination with iron to crush the iron siliconide, thus giving fine particles of silicon nitride of uniform particle size suitable for use as a starting substance for high-quality sintered products, at low costs and in large amounts. |
