US4251272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oxidation resistant porous abradable seal member for high temperature service
Assignee: Graftech International Holdings Inc
•
Filing: 1978-12-26
•
Granted: 1981-02-17
•
Expires: 1998-12-26
Abstract
Abstract Porous abradable sintered metal structures suitable for use as abradable seals are rendered oxidation resistant and thus suitable for high temperature service by introducing into the porous structure an intermetallic compound of aluminum with one of chromium, titanium, cobalt and nickel, which compound is then thermally reacted with the porous metal structures to form an aluminum alloy in the structure.
Inventors
- 👤 Raymond V. Sara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:51
CPC Classifications
F; F01; F01D; F01D11/00; F01D11/08; F01D11/12; F01D11/122; B; B22; B22F; B22F3/00; B22F3/10; B22F3/11; B22F3/114; B22F2998/00; B22F2998/10; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
145 words
Method of rendering a porous, abradable sintered metal structure comprising a base alloy of chromium with nickel or cobalt sufficiently oxidation resistant to be used at temperatures up to about 1050° C. without substantial loss of strength, porosity or abradability which comprises introducing into said porous sintered metal structure at least one powdered intermetallic compound of aluminum and an element selected from the group consisting of chromium, titanium, cobalt and nickel, the particles of said intermetallic compound powder being substantially smaller than the average pore size of said porous sintered metal structure, heating said metal structure to a temperature sufficient to cause said intermetallic compound to react with said base alloy to form a structure alloy of aluminum and chromium with at least one metal selected from the group consisting of nickel, cobalt and titanium, which structure alloy is substantially all beta and gamma phases.
Claim 2
Dependent Claim
145 words
Method of rendering a porous, abradable sintered metal structure comprising a base alloy of chromium with nickel or cobalt sufficiently oxidation resistant to be used at temperatures up to about 1050° C. without substantial loss of strength, porosity or abradability which comprises introducing into said porous sintered metal structure at least one powdered intermetallic compound of aluminum and an element selected from the group consisting of chromium, titanium, cobalt and nickel, the particles of said intermetallic compound powder being substantially smaller than the average pore size of said porous sintered metal structure, heating said metal structure to a temperature sufficient to cause said intermetallic compound to react with said base alloy to form a structure alloy of aluminum and chromium with at least one metal selected from the group consisting of nickel, cobalt and titanium, which structure alloy is substantially all beta and gamma phases.
Claim 3
Dependent Claim
34 words
A method according to claim 1 wherein the quantity of intermetallic compound introduced into said porous sintered metal structure is at least 7 weight percent of said porous sintered metal structure before said introduction.
Claim 4
Dependent Claim
33 words
A method according to claim 1 wherein the quantity of intermetallic compound introduced into said porous sintered metal compound is about 14 weight percent of said porous sintered metal structure before said introduction.
Claim 5
Dependent Claim
14 words
A method according to claim 1 wherein said base alloy comprises nickel and chromium.
Claim 6
Dependent Claim
14 words
A method according to claim 1 wherein said base alloy comprises chromium and cobalt.
Claim 7
Dependent Claim
15 words
A method according to claim 1 wherein said intermetallic compound is an aluminum chromium compound.
Claim 8
Dependent Claim
15 words
A method according to claim 1 wherein said intermetallic compound is an aluminum titanium compound.
Claim 9
Dependent Claim
15 words
A method according to claim 1 wherein said intermetallic compound is an aluminum cobalt compound.
Claim 10
Dependent Claim
15 words
A method according to claim 1 wherein said intermetallic compound is an aluminum nickel compound.
Claim 11
Dependent Claim
79 words
A method according to claim 1 wherein said intermetallic compound is at least one selected from the group consisting of Al 7 Cr, Al 11 Cr 2 , Al 4 Cr, Al 3 Cr, Al 3 Cr, Al 9 Cr 4 , Al 8 Cr 5 , AlCr 2 , Al 3 Ti, AlTi, Al 9 Co 2 , Al 13 Co 4 , Al 5 Co 2 , AlCo, Al 3 Ni, Al 3 Ni 2 and AlNi.
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) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |