US4123594A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metallic coated article of improved environmental resistance
Assignee: General Electric Co
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Filing: 1977-09-22
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Granted: 1978-10-31
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Expires: 1997-09-22
Abstract
Abstract A metallic article is provided with improved resistance to high temperature environmental conditions, particularly hot corrosion resistance, through the interdiffusion with the article substrate of a complex graded coating including an inner portion which includes Cr and at least one of the elements Fe, Co and Ni and an outer portion including Al and at least one element selected from Hf, Pt, Rh and Pd.
Inventors
- 👤 David R. Chang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:38
CPC Classifications
F; F01; F01D; F01D25/00; F01D25/007; C; C23; C23C; C23C28/00; C23C28/02; C23C28/021; C23C28/023; C23C28/028; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12458; Y10T428/12493; Y10T428/12736; Y10T428/12743; Y10T428/1275; Y10T428/12757; Y10T428/12771; Y10T428/12806; Y10T428/12826; Y10T428/12847; Y10T428/12854; Y10T428/12861; Y10T428/12875; Y10T428/12931
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
169 words
A metallic article comprising: a substrate of a superalloy based on an element selected from the group consisting of Fe, Co and Ni, and a graded coating diffused with said substrate to increase the hot corrosion resistance of the substrate, the graded coating consisting essentially of: (i) an inner coating portion adjacent to and diffused with the substrate, and consisting essentially of, by weight, 10-50% Cr, up to 30% Al, up to 10% Hf, up to 30% of elements selected from the group consisting of Pt, Rh and Pd, up to 3% Y, with the balance at least one element selected from the group consisting of Fe, Co and Ni, and elements diffused from the substrate and the outer coating portion, and (ii) an outer coating portion adjacent to and diffused with the inner coating portion, and consisting essentially of, by weight, 10-50% Al and 1-40% of elements selected from the group consisting of Hf, Pt, Rh and Pd, with the balance elements diffused from the inner coating portion.
Claim 2
Dependent Claim
169 words
A metallic article comprising: a substrate of a superalloy based on an element selected from the group consisting of Fe, Co and Ni, and a graded coating diffused with said substrate to increase the hot corrosion resistance of the substrate, the graded coating consisting essentially of: (i) an inner coating portion adjacent to and diffused with the substrate, and consisting essentially of, by weight, 10-50% Cr, up to 30% Al, up to 10% Hf, up to 30% of elements selected from the group consisting of Pt, Rh and Pd, up to 3% Y, with the balance at least one element selected from the group consisting of Fe, Co and Ni, and elements diffused from the substrate and the outer coating portion, and (ii) an outer coating portion adjacent to and diffused with the inner coating portion, and consisting essentially of, by weight, 10-50% Al and 1-40% of elements selected from the group consisting of Hf, Pt, Rh and Pd, with the balance elements diffused from the inner coating portion.
Claim 3
Dependent Claim
17 words
The article of claim 1 in which the outer coating portion includes 10-30% Al and 2-5% Hf.
Claim 4
Dependent Claim
17 words
The article of claim 1 in which the outer coating portion includes 10-30% Al and 5-40% Pt.
Claim 5
Dependent Claim
11 words
The article of claim 3 in which the Pt is 20-40%.
Claim 6
Dependent Claim
19 words
The article of claim 1 in which the outer coating portion includes 10-30% Al, 2-5% Hf and 20-40% Pt.
Claim 7
Dependent Claim
49 words
The article of claim 1 in which the inner coating portion consists essentially of, by weight, 8-20% Al, 10-40% Cr, up to 5% Hf, up to 20% Pt, up to 2% Y, with the balance at least one element selected from the group consisting of Fe, Co and Ni.
Claim 8
Dependent Claim
16 words
The article of claim 6 in which the Al is 8-16% and the Cr is 15-30%.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-30 | 1982-05-01 | 1982-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-30 | 1986-05-01 | 1986-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-30 | 1990-05-01 | 1990-10-31 | $7700.00 | Window Closed / Lapsed |