US4203733A
Expired / Lapsed
US
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Aluminum nitride sintered body coated with alumina
Assignee: Niterra Co Ltd
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Filing: 1978-08-16
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Granted: 1980-05-20
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Expires: 1998-08-16
Abstract
Abstract An aluminum nitride sintered body, especially suitable as a material for high-speed cutting tools, having on the surface thereof a coating of alumina crystals having an average particle diameter of about 2.5 microns or less.
Inventors
- 👤 Hiroshi Tanaka
- 👤 Yoshihiro Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:49
CPC Classifications
B; B23; B23B; B23B27/00; B23B27/14; B23B27/148; C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C16/403
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
34 words
An aluminum nitride sintered body consisting essentially of a sintered body of aluminum nitride with alumina crystals having an average particle diameter of 2.5 microns or less on the surface of the sintered body.
Claim 2
Dependent Claim
34 words
An aluminum nitride sintered body consisting essentially of a sintered body of aluminum nitride with alumina crystals having an average particle diameter of 2.5 microns or less on the surface of the sintered body.
Claim 3
Dependent Claim
54 words
The aluminum nitride sintered body of claim 1, wherein the aluminum nitride sintered body comprises at least 97% by volume of the aluminum nitride and about 3% by volume or less, calculated as the metal, of a member selected from the group consisting of Mo, W, Mo 2 C and WC and mixtures thereof.
Claim 4
Dependent Claim
38 words
The aluminum nitride sintered body of claim 1, wherein the aluminum nitride sintered body contains about 3% by volume or less of a member selected from the group consisting of Y 2 O 3 and SiO 2 .
Claim 5
Dependent Claim
28 words
The aluminum nitride sintered body of claim 1, 2 or 3, wherein the aluminum nitride sintered body has a density of at least 95% of the theoretical density.
Claim 6
Dependent Claim
13 words
A high-speed cutting tool comprising the aluminum nitride sintered body of claim 1.
Claim 7
Dependent Claim
26 words
The aluminum nitride sintered body of claim 1, wherein the alumina crystals are present on the surface at a thickness of about 2 to 30 microns.
Claim 8
Dependent Claim
14 words
The aluminum nitride sintered body of claim 6, wherein said thickness is 2-10 microns.
Claim 9
Dependent Claim
25 words
The aluminum nitride sintered body of claim 1, wherein the aluminum nitride sintered body has a density of at least 97% of the theoretical density.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-05-20 | 1983-11-19 | 1984-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-20 | 1987-11-19 | 1988-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-20 | 1991-11-19 | 1992-05-20 | $7700.00 | Window Closed / Lapsed |