Compositions: ceramic – Ceramic compositions – Carbide or oxycarbide containing
Patent
1994-06-23
1998-03-03
Group, Karl
Compositions: ceramic
Ceramic compositions
Carbide or oxycarbide containing
501 97, 501 95, C04B 35577
Patent
active
057233926
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.
REFERENCES:
patent: 4863881 (1989-09-01), Ahrens et al.
patent: 5132257 (1992-07-01), Kodama et al.
patent: 5160508 (1992-11-01), Pyzik et al.
patent: 5196386 (1993-03-01), Furrse et al.
patent: 5200373 (1993-04-01), Yasufomi et al.
patent: 5358912 (1994-10-01), Freitag et al.
Ezis Andre
Shih C. James
Cercom Inc.
Group Karl
Spiegel H. Jay
LandOfFree
In-situ grown whisker reinforced ceramics does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with In-situ grown whisker reinforced ceramics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and In-situ grown whisker reinforced ceramics will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2247282