Patent US4089736A successfully refreshed from Google Patents.
US4089736A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of removing Al-Cr-Co coatings from nickel alloy substrates
Assignee: Rolls Royce PLC
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Filing: 1977-04-11
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Granted: 1978-05-16
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Expires: 1997-04-11
Abstract
Abstract A method of removing a coating containing aluminium and chromium in combination with cobalt from a nickel base alloy substrate. The coated substrate is immersed in a solution containing the following constituents (by weight): Ferric Sulphate; 6-14% Hydrochloric Acid; 3.5-11% Water; Remainder When substantially all of the coating has been dissolved, the substrate is removed from the solution.
Inventors
- 👤 Maurice Fisher
- 👤 Terence Walter Maber
- 👤 Colin Garry Lilly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:49
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/44
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
67 words
A method of removing a coating from a substrate, said coating containing aluminium and chromium in combination with cobalt, said substrate being a nickel base alloy, said method comprising immersing said coated substrate in a solution containing the following constituents (by weight): Ferric Sulphate; 6-14% Hydrochloric Acid; 3.5-11% Water; Remainder until substantially all of the coating has been dissolved and then removing the substrate from the solution.
Claim 2
Independent Claim
67 words
A method of removing a coating from a substrate, said coating containing aluminium and chromium in combination with cobalt, said substrate being a nickel base alloy, said method comprising immersing said coated substrate in a solution containing the following constituents (by weight): Ferric Sulphate; 6-14% Hydrochloric Acid; 3.5-11% Water; Remainder until substantially all of the coating has been dissolved and then removing the substrate from the solution.
Claim 3
Independent Claim
23 words
A method of removing a coating from a substrate as claimed in clam 1 wherein said solution contains 8-10% by weight ferric sulphate.
Claim 4
Dependent Claim
23 words
A method of removing a coating from a substrate as claimed in claim 1 wherein said solution contains 7-9% by weight hydrochloric acid.
Claim 5
Dependent Claim
27 words
A method of removing a coating from a substrate as claimed in claim 1 wherein said solution is maintained at a temperature between 15° and 75° C.
Claim 6
Dependent Claim
27 words
A method of removing a coating from a substrate as claimed in claim 4 wherein said solution is maintained at a temperature between 45° and 55° C.
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) | 1981-05-15 | 1981-11-14 | 1982-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-15 | 1985-11-14 | 1986-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-15 | 1989-11-14 | 1990-05-16 | $7700.00 | Window Closed / Lapsed |