| 摘要 |
PROBLEM TO BE SOLVED: To provide grinding/dispersion media that consist of a silicon nitride sintered material and can be stably used over a long period without causing increase in wear or sudden increase in wear at a point of time, which increase in wear is usually caused when conventional grinding/dispersion media are used, and also excellent in wear resistance, durability and impact resistance and can sufficiently-satisfactorily be used as raw material grinding/dispersion media for producing an inorganic high-functional material, by adopting silicon nitride that is conventionally not used as raw material grinding/dispersion media for producing an inorganic high-functional material, as a material of the media, and also to provide a production process for the media. SOLUTION: The media consist of a silicon nitride sintered material which contains 2-5 wt.% of Al2O3, 3-8 wt.% of Y2O3 and 6-10 wt.% of the total of Al2O3 and Y2O3 and has a >=3.10 g/cm3 bulk density, a Vickers hardness of >=1,300, a >=400 MPa collapse strength, a 3 mm media size (in diameter) and a media circularity factor of >=0.9. |
