US4412009A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sintered Si3 N4 body
Assignee: Toshiba Corp
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Filing: 1981-09-23
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Granted: 1983-10-25
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Expires: 2001-09-23
Abstract
Abstract Disclosed is a method of producing a sintered body of ceramics, wherein a powder mixture consisting, essentially of at most 10%, exclusive of 0%, by weight of yttrium oxide, at most 10%, exclusive of 0%, by weight of aluminum oxide, at most 10%, exclusive of 0%, by weight of aluminum nitride, at most 5%, exclusive of 0%, by weight of at least one material selected from the group consisting of titanium oxide, magnesium oxide and zirconium oxide, and the balance essentially of silicon nitride is sintered under a non-oxidizing atmosphere.
Inventors
- 👤 Michiyasu Komatsu
- 👤 Akihiko Tsuge
- 👤 Katsutoshi Komeya
- 👤 Akio Ando
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:57
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/593; C04B35/597
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
86 words
A sintered ceramic body consisting essentially of at most 10%, exclusive of 0%, by weight of yttrium oxide; at most 10%, exclusive of 0%, by weight of aluminum nitride; at most 10%, exclusive of 0%, by weight of aluminum nitride; at most 5%, exclusive of 0%, by weight of at least one material selected from the group consisting of titanium oxide, magnesium oxide and zirconium oxide; and the balance essentially of silicon nitride; wherein said sintered ceramic body has a relative density of at least 95.1%.
Claim 2
Dependent Claim
86 words
A sintered ceramic body consisting essentially of at most 10%, exclusive of 0%, by weight of yttrium oxide; at most 10%, exclusive of 0%, by weight of aluminum nitride; at most 10%, exclusive of 0%, by weight of aluminum nitride; at most 5%, exclusive of 0%, by weight of at least one material selected from the group consisting of titanium oxide, magnesium oxide and zirconium oxide; and the balance essentially of silicon nitride; wherein said sintered ceramic body has a relative density of at least 95.1%.
Claim 3
Dependent Claim
25 words
The sintered ceramic body according to claim 1, wherein the total amount of yttrium oxide and aluminum oxide ranges between 3 and 15% by weight.
Claim 4
Dependent Claim
27 words
The sintered ceramic body according to claim 1 or 2, wherein the total amount of aluminum nitride and aluminum oxide ranges between 2 and 15% by weight.
Claim 5
Dependent Claim
36 words
The sintered ceramic body according to claim 3, wherein the amount of at least one material selected from the group consisting of titanium oxide, magnesium oxide and zirconium oxide ranges between 0.05 and 3% by weight.
Claim 6
Dependent Claim
21 words
The sintered ceramic body according to claim 1, wherein the amount of silicon nitride ranges between 70 and 94% by weight.
References Cited (Backward Citations)
US3969125A
Cited
US4066468A
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US3991148A
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US3830652A
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US4143107A
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US4127416A
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US4127416B1
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-24 | 1987-04-25 | 1987-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-24 | 1991-04-25 | 1991-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-24 | 1995-04-25 | 1995-10-25 | $7700.00 | Window Closed / Lapsed |