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US4753902A
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Transformation toughened zirconia-titania-yttria ceramic alloys
Assignee: Corning Glass Works
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Filing: 1986-11-24
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Granted: 1988-06-28
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Expires: 2006-11-24
Abstract
Abstract This invention is directed to the production of ceramic alloys consisting essentially of ZrO 2 , titania, and yttria or rare earth oxides such as gadolinia, ytterbia, neodymia, and ceria. Mole % concentration values as low as 0.25 mole % for yttria have been found to provide a hard and tough ceramic alloy in the presence of the titania-zirconia body. These compositions have been found to produce effective hard and tough ceramic bodies when mixed with refractory fibers and/or whiskers and hard refractory ceramics.
Inventors
- 👤 Thomas D. Ketcham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:08
CPC Classifications
A; A01; A01B; A01B11/00; C; C04; C04B; C04B35/00; C04B35/01; C04B35/48; C04B35/49; C04B35/71; C04B35/78; C04B35/80
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
171 words
An improved ceramic composition consisting essentially of a sintered partially stabilized ZrO 2 ceramic alloy whose composition is selected from: (a) composition A consisting essentially of a sintered ceramic alloy consisting essentially of 45 to 94.75 mole percent zirconia, 5 to 45 mole percent titania, and 0.25 to 10 mole percent rare earth oxide selected from the group consisting of Gd 2 O 3 , Yb 2 O 3 , Nd 2 O 3 , Tb 2 O 3 , Pr 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Sm 2 O 3 , and Er 2 O 3 , (b) composition B consisting essentially of a sintered ceramic alloy consisting essentially of 48 to 94.75 mole percent zirconia, 5 to 45 mole percent titania and 0.25 to 7 mole percent yttria, and (c) composition C consisting essentially of a sintered ceramic alloy consisting essentially of 35 to 93.5 mole percent zirconia, 5 to 45 mole percent titania, and 1.5 to 20 mole % ceria.
Claim 2
Dependent Claim
171 words
An improved ceramic composition consisting essentially of a sintered partially stabilized ZrO 2 ceramic alloy whose composition is selected from: (a) composition A consisting essentially of a sintered ceramic alloy consisting essentially of 45 to 94.75 mole percent zirconia, 5 to 45 mole percent titania, and 0.25 to 10 mole percent rare earth oxide selected from the group consisting of Gd 2 O 3 , Yb 2 O 3 , Nd 2 O 3 , Tb 2 O 3 , Pr 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Sm 2 O 3 , and Er 2 O 3 , (b) composition B consisting essentially of a sintered ceramic alloy consisting essentially of 48 to 94.75 mole percent zirconia, 5 to 45 mole percent titania and 0.25 to 7 mole percent yttria, and (c) composition C consisting essentially of a sintered ceramic alloy consisting essentially of 35 to 93.5 mole percent zirconia, 5 to 45 mole percent titania, and 1.5 to 20 mole % ceria.
Claim 3
Dependent Claim
14 words
The composition as defined in claim 1 wherein the selected composition is composition A.
Claim 4
Dependent Claim
14 words
The composition as defined in claim 1 wherein the selected composition is composition B.
Claim 5
Dependent Claim
14 words
The composition as defined in claim 1 wherein the selected composition is composition C.
Claim 6
Dependent Claim
18 words
A ceramic composition of claim 1 consisting of fine grain size crystals less than 4 microns in size.
Claim 7
Dependent Claim
68 words
A ceramic composition of claim 2 consisting essentially of 0.5 to 4.0 mole percent rare earth oxide selected from the group consisting of Gd 2 O 3 , Yb 2 O 3 , Nd 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Pr 2 O 3 , Sm 2 O 3 , Tb 2 O 3 and Er 2 O 3 .
Claim 8
Dependent Claim
42 words
An improved ceramic composition consisting essentially of a sintered partially-stabilized ceramic alloy having a composition consisting essentially of 0.5 to 4.0 mole percent yttria or a rare earth oxide, 22 to 45 mole percent titania, and 51 to 77.5 mole percent zirconia.
Claim 9
Dependent Claim
42 words
An improved ceramic composition consisting essentially of a sintered partially-stabilized ceramic alloy having a composition consisting essentially of 0.5 to 4.0 mole percent yttria or a rare earth oxide, 22 to 45 mole percent titania, and 51 to 77.5 mole percent zirconia.
Claim 10
Dependent Claim
28 words
A ceramic composition of claim 4 consisting essentially of 1.5 to 16 mole percent ceria, 22 to 45 mole percent titania, and 39 to 76.5 mole percent zirconia.
Claim 11
Dependent Claim
67 words
A ceramic composition of claim 2 consisting essentially of 0.5 to 3.0 mole percent rare earth oxide selected from the group of Gd 2 O 3 , Yb 2 O 3 , Nd 2 O 3 , Pr 2 O 3 , Tb 2 O 3 , Ho 2 O 3 , Sm 2 O 3 , Dy 2 O 3 and Er 2 O 3 .
Claim 12
Dependent Claim
29 words
A ceramic composition of claim 3 consisting essentially of 0.5 to 3.0 mole percent of yttria, 25 to 40 mole percent titania, and 57 to 74.5 mole percent zirconia.
Claim 13
Dependent Claim
28 words
A ceramic composition of claim 4 consisting essentially of 1.5 to 8 mole percent ceria, 25 to 40 mole percent titania, and 52 to 73.5 mole percent zirconia.
Claim 14
Dependent Claim
62 words
A ceramic body consisting essentially of at least 5% by volume of a ceramic alloy according to claim 1 with a remainder being a hard refractory ceramic selected from the group consisting of α-alumina, β-alumina, β'-alumina, Al 2 O 3 -Cr 2 O 3 solid solution, mullite, sialon, nasicon, silicon carbide, silicon nitride, spinel, titanium carbide, titanium diboride, zircon, and zirconium carbide.
Claim 15
Dependent Claim
54 words
A ceramic composite body consisting essentially of up to 80% by volume refractory ceramic fibers and/or whiskers selected from the group consisting of alumina, mullite, sialon, silicon carbide, silicon nitride, AlN, BN, B 4 C, zircon, silicon oxycarbide, and spinel and at least 5% by volume of a ceramic alloy according to claim 1.
Claim 16
Dependent Claim
20 words
A ceramic composition of claim 1 wherein the predominant crystal phases present are tetragonal or monoclinic or a combination thereof.
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) | 1991-06-28 | 1991-12-28 | 1992-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-28 | 1995-12-28 | 1996-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-28 | 1999-12-28 | 2000-06-28 | $7700.00 | Window Closed / Lapsed |