The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 03, 1998
Filed:
Jun. 23, 1994
Andre Ezis, Vista, CA (US);
C James Shih, Vista, CA (US);
Cercom, Inc., Vista, CA (US);
Abstract
In-situ Si.sub.3 N.sub.4 whisker growth mechanisms have enhanced the microstructure of ceramic materials such as SiC through controlled growth of elongated beta-type Silicon Nitride grains. During liquid phase sintering at temperatures not exceeding 1850.degree. C., alpha-type Silicon Nitride dissolves into the liquid phase and reprecipitates as an elongated or acicular beta modification. The Si.sub.3 N.sub.4 reinforced microstructures can be formed by the controlled recrystallization of beta-type Silicon Nitride. In-situ whisker growth is enhanced or optimized through the use of thermal treatments and/or additions of seed materials. Finely divided beta-type Silicon Nitride particles which are insoluble in the liquid phase during sintering, and therefore have been used to provide nucleation sites for whisker growth are employed. Thermal treatments have been designed to promote directional growth (elongation) as opposed to development of less elongated type grains.