Carl Eugene Bates

US Patent:

46907904, Sep 1, 1987

Filed:

Jul 23, 1985

Appl. No.:

6/758184

Inventors:

Carl H. Bates - South Amboy NJ

Assignee:

Stemcor Corporation - Cleveland OH

International Classification:

C04B 3556
C04B 3558

US Classification:

264 63

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.