US4801564A
Expired / Lapsed
US
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High-toughness ceramic tool materials
Assignee: Niterra Co Ltd
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Filing: 1986-06-17
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Granted: 1989-01-31
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Expires: 2006-06-17
Abstract
Abstract A high-toughness ceramic tool material consisting essentially of 50-95% by volume of a main sialon base phase wherein at least 10% by volume of the sialon base phase consists of alpha-sialon, and 5-50% by volume of a SiC whisker phase. This ceramic material is produced by sintering a composition comprising: 50-95% by volume of a sialon forming component such that at least 10% by volume, calculated on the entire sialon, of alpha-sialon is formed, and 5-50% volume of SiC whiskers; said sialon forming component consisting essentially of 50-95% by weight of Si 3 N 4 and 50-50% by weight of constituents of sialon-consistituting elements other than Si 3 N 4 , said constituents consisting of a mixture of AlN and Al 2 O 3 , and at least one oxide selected from the group consisting of oxides of yttrium and rare earth elements, said mixture of AlN and Al 2 O 3 containing at least 60% by weight of AlN calculated on said mixture, and said mixture and said at least one oxide being in a ratio of 1:3 to 3:1 by weight. The ceramic tool has high toughness and wear-resistance.
Inventors
- 👤 Hidetoshi Baba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:51
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/515; C04B35/58; C04B35/597
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
40 words
A high-toughness ceramic tool material consisting essentially of 50-95% by volume of a main sialon base phase, wherein at least 10% by volume of the sialon base phase consists of alpha-sialon, and 5-50% by volume of a SiC whisker phase.
Claim 2
Dependent Claim
40 words
A high-toughness ceramic tool material consisting essentially of 50-95% by volume of a main sialon base phase, wherein at least 10% by volume of the sialon base phase consists of alpha-sialon, and 5-50% by volume of a SiC whisker phase.
Claim 3
Dependent Claim
34 words
A ceramic tool material as defined in claim 1, wherein 50-95% by volume of the sialon base phase consists of 50 to 95% by volume of sialon calculated on the main sialon base phase.
Claim 4
Dependent Claim
24 words
A ceramic tool material as defined in claim 2, wherein at least 30% by volume of the main sialon base phase consists of alpha-sialon.
Claim 5
Dependent Claim
24 words
A ceramic tool material as defined in claim 3, wherein at least 50% by volume of the main sialon base phase consists of alpha-sialon.
Claim 6
Dependent Claim
21 words
A ceramic tool as defined in claim 1, wherein the SiC whisker phase occupies 10-40% by volume of the entire material.
Claim 7
Dependent Claim
21 words
A ceramic tool as defined in claim 5, wherein the SiC whisker phase occupies 20-30% by volume of the entire material.
Claim 8
Dependent Claim
24 words
A ceramic tool as defined in claim 1, wherein the main sialon base phase has an average crystal grain size not exceeding 5 micrometers.
Claim 9
Dependent Claim
21 words
A ceramic tool as defined in claim 1, which has a relative density of at least 95% of the theoretical density.
Claim 10
Dependent Claim
30 words
A ceramic tool as defined in claim 1, which further includes at least one element derived from sintering aids which are selected from oxides of yttrium and rare earth elements.
Claim 11
Dependent Claim
148 words
A high toughness ceramic tool material composition consisting essentially of: 50-95% by volume of a component forming a silaon phase such that at least 10% by volume, calculated on the entire sialon, of alpha-sialon is formed, and 5-50% by volume of SiC whiskers disposed in said component; said component consisting essentially of 50-95% by weight of Si 3 N 4 and 5-50% by weight of constituents of sialon-constituting elements other than Si 3 N 4 , said constituents consisting of a mixture of AlN and Al 2 O 3 , and at least one oxide selected from the group consisting of oxides of yttrium and rare earth elements, said mixture of AlN and Al 2 O 3 containing at least 60% by weight of AlN calculatd on said mixture, and said mixture and said at least one oxide being in a ratio of 1:3 to 3:1 by weight.
Claim 12
Dependent Claim
148 words
A high toughness ceramic tool material composition consisting essentially of: 50-95% by volume of a component forming a silaon phase such that at least 10% by volume, calculated on the entire sialon, of alpha-sialon is formed, and 5-50% by volume of SiC whiskers disposed in said component; said component consisting essentially of 50-95% by weight of Si 3 N 4 and 5-50% by weight of constituents of sialon-constituting elements other than Si 3 N 4 , said constituents consisting of a mixture of AlN and Al 2 O 3 , and at least one oxide selected from the group consisting of oxides of yttrium and rare earth elements, said mixture of AlN and Al 2 O 3 containing at least 60% by weight of AlN calculatd on said mixture, and said mixture and said at least one oxide being in a ratio of 1:3 to 3:1 by weight.
Claim 13
Dependent Claim
17 words
A composition as defined in claim 10, wherein the amount of SiC whiskers is 10-40% by volume.
Claim 14
Dependent Claim
18 words
A composition as defined in claim 11, wherein the SiC amount of SiC whiskers is 20-30% by volume.
Claim 15
Dependent Claim
23 words
A composition as defined in claim 10, wherein the SiC whiskers have a length of 5-200 micrometer and a diameter of 0.05-1.5 micrometer.
Claim 16
Dependent Claim
28 words
A composition as defined in claim 10, wherein said at least one oxide is Y 2 O 3 , Dy 2 O 3 , and/or CeO 2 .
Claim 17
Dependent Claim
28 words
A composition as defied in claim 10, wherein AlN amounts to at least 70% by weight calculated on the mixture of AlN and Al 2 O 3 .
Claim 18
Dependent Claim
23 words
A composition as defined in claim 10, wherein said mixture and said oxide are in a ratio of 1:2 to 2:1 by weight.
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) | 1992-01-31 | 1992-08-01 | 1993-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-31 | 1996-08-01 | 1997-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-31 | 2000-08-01 | 2001-01-31 | $7700.00 | Window Closed / Lapsed |