US4247249A
Expired / Lapsed
US
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Turbine engine shroud
Assignee: General Electric Co
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Filing: 1978-09-22
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Granted: 1981-01-27
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Expires: 1998-09-22
Abstract
Abstract High temperature resistant turbine engine shrouds are formed of an amphoteric refractory oxide, a phosphate binding agent and optionally a stabilizer, reinforcement and/or porosity controller.
Inventors
- 👤 Paul A. Siemers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:21
CPC Classifications
F; F01; F01D; F01D11/00; F01D11/08; F01D11/12; F01D11/122; Y; Y02; Y02T; Y02T50/00; Y02T50/60; Y10; Y10S; Y10S277/00; Y10S277/935; Y10S277/939; Y10S277/941; Y10S277/943; Y10S60/00; Y10S60/909
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
129 words
In a gas turbine engine, a shroud comprising a plurality of arcuate segments disposed in end to end relationship to surround the tips of the rotor blades of the engine wherein each segment has a sealing surface which opposes the tips of the blades wherein the sealing surface is formed of an amphoteric refractory oxide matrix of material selected from ZrO 2 , Al 2 O 3 , Ce 2 O, ThO 2 and HfO 2 or mixture, a phosphate binding agent stable above about 1350° C., and from 0 to 50% by weight of the matrix material of a stabilizer selected from Y 2 O 3 , MgO, CaO, rare earth oxide or mixture and from 0 to 25% by weight of the matrix material of a filler.
Claim 2
Dependent Claim
129 words
In a gas turbine engine, a shroud comprising a plurality of arcuate segments disposed in end to end relationship to surround the tips of the rotor blades of the engine wherein each segment has a sealing surface which opposes the tips of the blades wherein the sealing surface is formed of an amphoteric refractory oxide matrix of material selected from ZrO 2 , Al 2 O 3 , Ce 2 O, ThO 2 and HfO 2 or mixture, a phosphate binding agent stable above about 1350° C., and from 0 to 50% by weight of the matrix material of a stabilizer selected from Y 2 O 3 , MgO, CaO, rare earth oxide or mixture and from 0 to 25% by weight of the matrix material of a filler.
Claim 3
Dependent Claim
14 words
The shroud of claim 1 wherein the amphoteric refractory oxide is ZrO 2 .
Claim 4
Dependent Claim
21 words
The shroud of claim 2 wherein from 4 to 50% of a stabilizer is employed of Y 2 O 3 .
Claim 5
Dependent Claim
21 words
The shroud of claim 1 wherein a mixture of phosphate is employed of H 3 PO 4 and AlPO 4 .
Claim 6
Dependent Claim
26 words
The shroud of claim 1 wherein a filler is employed of up to 25% of the matrix material selected from graphite, silicon carbide whisker and mixtures.
Claim 7
Dependent Claim
34 words
The shroud of claim 1 wherein the matrix material is selected from ZrO 2 , HfO 2 and mixtures and the stabilizer is selected from Y 2 O 3 , MgO, CaO and mixtures.
Claim 8
Dependent Claim
29 words
The shroud of claim 1 wherein the sealing surface is formed of ZrO 2 stabilized with Y 2 O 3 , H 3 PO 4 and silicon carbide whiskers.
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) | 1984-01-27 | 1984-07-28 | 1985-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-27 | 1988-07-28 | 1989-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-27 | 1992-07-28 | 1993-01-27 | $7700.00 | Window Closed / Lapsed |