Silicon nitride/silicon carbide composition and articles thereof
US4690790A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 23, 1985 |
| Grant date | Sep 1, 1987 |
| Priority date | — |
| Expiry date | Jul 23, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/565
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Corrosion and thermal shock resistant high silicon nitride content silicon nitride-bonded silicon carbide article, e.g., nozzle for transfer of molten metal, is prepared by combining finely divided silicon metal, silicon carbide grain with processing aids, forming the mixture into an article, and firing the article in nitrogen. Even higher silicon nitride content is obtained by crushing the article to obtain a precursor grog material, combining this grog with more finely divided silicon metal and processing aids, forming the mixture into an article and firing in nitrogen. Silicon nitride content of up to about 70 weight percent may be obtained with single mixing and firing; up to about 98 weight percent with use of nitrided precusor grog, remixing and firing. With reiteration, a silicon nitride content of essentially 100 weight percent can be approached.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.