Abrasive tool making process – material – or composition – With inorganic material – Metal or metal oxide
Patent
1989-02-28
1990-04-24
Bell, Mark L.
Abrasive tool making process, material, or composition
With inorganic material
Metal or metal oxide
501 10, 501 95, 501 97, 501 98, C04B 3558
Patent
active
049196898
ABSTRACT:
A process for preparing a self-reinforced silicon nitride ceramic body of high fracture toughness comprising hot-pressing a powder mixture containing silicon nitride, magnesium oxide, yttrium oxide and calcium oxide under conditions such that densification and the in situ formation of .beta.-silicon nitride whiskers having a high aspect ratio occur. A novel silicon nitride ceramic of high fracture toughness is disclosed comprising a .beta.-silicon nitride crystalline phase wherein at least about 20 volume percent of the phase is in the form of whiskers having an average aspect ratio of at least about 2.5; a glassy second phase containing magnesium oxide, yttrium oxide, calcium oxide, and silica in a total amount not greater than about 35 weight percent; and not greater than about 10 weight percent of the total weight as other phases.
REFERENCES:
patent: 3950464 (1976-04-01), Masaki
patent: 4004937 (1977-01-01), Masaki
patent: 4025351 (1977-05-01), Masaki
patent: 4046580 (1977-09-01), Ishii et al.
patent: 4097293 (1978-06-01), Komeya et al.
patent: 4119689 (1978-10-01), Prochazka et al.
patent: 4179301 (1979-12-01), Buljan
patent: 4218257 (1980-08-01), Oda
patent: 4227842 (1980-10-01), Samanta et al.
patent: 4279657 (1981-07-01), Greskovich
patent: 4296065 (1981-10-01), Ishii et al.
patent: 4323325 (1982-04-01), Samanta et al.
patent: 4406668 (1983-09-01), Sarin et al.
patent: 4407970 (1983-10-01), Komatsu et al.
patent: 4511525 (1985-04-01), Tsuge et al.
patent: 4543345 (1985-09-01), Wei
patent: 4603116 (1986-07-01), Smith et al.
patent: 4609633 (1986-09-01), Fukuhara
patent: 4652276 (1987-03-01), Burden
patent: 4699890 (1987-10-01), Matsui
patent: 4717693 (1988-01-01), Wittmer
patent: 4734234 (1988-03-01), Sterzel
patent: 4753764 (1988-06-01), Kamijo et al.
Derwent 82:51169E.
Derwent 87:098199/14.
Akihiko Tsuge et al., Journal of the American Ceramics Society, 58, 323-326, (1975).
F. F. Lange, Journal of the American Ceramics Society, 62, 1369-1374, (1983).
Chemical Abstracts 105:157787w, (1986).
Beaman Donald R.
Dubensky William J.
Pyzik Aleksander J.
Schwarz Douglas B.
Bell Mark L.
Group Karl
Howard D. R.
The Dow Chemical Company
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