Patent US4383957A successfully refreshed from Google Patents.
US4383957A
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Method of sintering a ceramic composition
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1981-05-20
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Granted: 1983-05-17
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Expires: 2001-05-20
Abstract
Abstract A ceramic sintered body with a high density and high surface smoothness is obtained by sintering a ceramic composition comprising oxides as a substantial or partial component in an atmosphere of CO gas or in a mixture of CO gas and an inert gas.
Inventors
- 👤 Akira Yamakawa
- 👤 Akira Doi
- 👤 Yoshihiko Doi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:07
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/117; C04B35/119; C04B35/622; C04B35/64
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
78 words
A method of sintering a ceramic material which comprises sintering at a temperature of 1200° to 2000° C., a ceramic composition comprising oxides selected from the group consisting of Al 2 O 3 , ZrO 2 and mixtures thereof as a substantial or partial component in an atmosphere of CO gas or mixed gases of CO gas and an inert gas, wherein the partial pressure of the CO gas ranges from 5 mm Hg to 760 mm Hg.
Claim 2
Independent Claim
78 words
A method of sintering a ceramic material which comprises sintering at a temperature of 1200° to 2000° C., a ceramic composition comprising oxides selected from the group consisting of Al 2 O 3 , ZrO 2 and mixtures thereof as a substantial or partial component in an atmosphere of CO gas or mixed gases of CO gas and an inert gas, wherein the partial pressure of the CO gas ranges from 5 mm Hg to 760 mm Hg.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein the inert gas is selected from the group consisting of argon, helium and nitrogen.
Claim 4
Dependent Claim
68 words
The method of claim 1, wherein the ceramic composition comprising oxides as a partial component is composed of predominant phases of aluminum oxide and a B1 type solid solution represented by M(C 1 N m O n ) in which M is a metal of Group IVa, Va or VIa and 1, m and n are molar ratios of carbon, nitrogen and oxygen with the relationship of 1+m+n=1.
Claim 5
Dependent Claim
19 words
The method of claim 1, wherein the sintering is carried out after removing adsorbed gases from the ceramic composition.
Claim 6
Dependent Claim
44 words
A method according to claim 1 in which a gas non-permeable sintered body is produced from said sintering method in which the said sintered body has a relative density of at least 95% and said sintered body is subjected to a hot isostatic press.
References Cited (Backward Citations)
GB665373A
Cited
US3455682A
Cited
US3469976A
Cited
US3562371A
Cited
US3574645A
Cited
US3792142A
Cited
US4041123A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-16 | 1986-11-15 | 1987-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-16 | 1990-11-15 | 1991-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-16 | 1994-11-15 | 1995-05-17 | $7700.00 | Window Closed / Lapsed |