US5538796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermal barrier coating system having no bond coat
Assignee: General Electric Co
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Filing: 1992-10-13
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Granted: 1996-07-23
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Expires: 2012-10-13
Abstract
Abstract A coated article is prepared by melting and casting an article substrate formed of a nickel-base superalloy. The article substrate is heated in a hydrogen-containing atmosphere at a temperature of at least 2000° F. for a period sufficient to desulfurize the substrate to a sulfur content of less than about 1 part per million. Optionally, an aluminum-oxide environmental coating is provided overlying the substrate. A ceramic thermal barrier coating is applied overlying the substrate. Significantly, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Inventors
- 👤 Jon C. Schaffer
- 👤 Wendy H. Murphy
- 👤 William B. Connor
- 👤 Bangalore A. Nagaraj
- 👤 Himanshu B. Vakil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:12
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/28; F01D5/288; C; C23; C23C; C23C14/00; C23C14/02; C23C14/06; C23C14/08; C23C14/083; F05; F05D; F05D2230/00; F05D2230/90; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
58 words
A method for preparing a coated article, comprising the steps of: furnishing an aluminum-bearing nickel base superalloy article substrate; thereafter desulfurizing the article substrate; and applying by a physical vapor deposition process a ceramic thermal barrier coating overlying the substrate, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Claim 2
Independent Claim
58 words
A method for preparing a coated article, comprising the steps of: furnishing an aluminum-bearing nickel base superalloy article substrate; thereafter desulfurizing the article substrate; and applying by a physical vapor deposition process a ceramic thermal barrier coating overlying the substrate, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Claim 3
Dependent Claim
24 words
The method of claim 1, wherein the step of furnishing includes the steps of melting and casting an alloy that forms the article substrate.
Claim 4
Dependent Claim
39 words
The method of claim 1, wherein the step of desulfurizing includes the step of heating the article substrate to an elevated temperature in the presence of a gaseous reactive agent that reacts with sulfur to form a gaseous sulfide.
Claim 5
Dependent Claim
22 words
The method of claim 3, wherein the step of heating includes heating the substrate to a temperature of at least 2000° F.
Claim 6
Dependent Claim
12 words
The method of claim 3, wherein the gaseous reactive agent comprises hydrogen.
Claim 7
Dependent Claim
37 words
The method of claim 1, wherein the step of applying the thermal barrier coating by a physical vapor deposition process is selected from the group of physical vapor deposition processes consisting of electron beam deposition and sputtering.
Claim 8
Dependent Claim
13 words
The method of claim 6, wherein the thermal barrier coating is yttria-stabilized zirconia.
Claim 9
Dependent Claim
33 words
The method of claim 1, including the additional step, after the step of desulfurizing and before the step of applying a thermal barrier coating, of providing an aluminum-oxide environmental coating overlying the substrate.
Claim 10
Dependent Claim
9 words
An article prepared by the process of claim 1.
Claim 11
Independent Claim
72 words
A method for preparing a coated article, comprising the steps of: furnishing an article substrate formed of a nickel-base superalloy; thereafter heating the article substrate in a gaseous reactive agent for a period sufficient to desulfurize the substrate; and applying a ceramic thermal barrier coating by a physical vapor deposition process overlying the substrate, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Claim 12
Independent Claim
72 words
A method for preparing a coated article, comprising the steps of: furnishing an article substrate formed of a nickel-base superalloy; thereafter heating the article substrate in a gaseous reactive agent for a period sufficient to desulfurize the substrate; and applying a ceramic thermal barrier coating by a physical vapor deposition process overlying the substrate, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Claim 13
Dependent Claim
11 words
The method of claim 10, wherein the reactive agent comprises hydrogen.
Claim 14
Dependent Claim
21 words
The method of claim 10, wherein the step of heating heats the article to a temperature of at least 2000° F.
Claim 15
Dependent Claim
36 words
The method of claim 10, wherein the step of providing includes the step of overcoating at least a portion of the surface of the article with an environmental coating that forms an aluminum-oxide scale upon heating.
Claim 16
Dependent Claim
24 words
The method of claim 10, wherein the step of providing includes the step of depositing an aluminum-oxide scale on the surface of the article.
Claim 17
Dependent Claim
37 words
The method of claim 10, wherein the step of applying the thermal barrier coating by a physical vapor deposition process is selected from the group of physical vapor deposition processes consisting of electron beam deposition and sputtering.
Claim 18
Dependent Claim
9 words
An article prepared by the process of claim 10.
Claim 19
Dependent Claim
19 words
The method of claim 10 further including a step of providing an aluminum oxide environmental coating overlying the substrate.
Claim 20
Dependent Claim
17 words
The method of claim 17 wherein the aluminum oxide environmental coating is thermally grown onto the substrate.
Claim 21
Dependent Claim
15 words
The method of claim 17 wherein the ceramic thermal barrier coating overlies the environmental coating.
Claim 22
Independent Claim
70 words
A method for preparing a coated article, comprising the steps of: furnishing an article substrate formed of a nickel-base superalloy, the superalloy having a sulfur content of less than about 1 part per million by weight; and applying, using a low sulfur application method, a ceramic thermal barrier coating overlying the substrate, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Claim 23
Independent Claim
70 words
A method for preparing a coated article, comprising the steps of: furnishing an article substrate formed of a nickel-base superalloy, the superalloy having a sulfur content of less than about 1 part per million by weight; and applying, using a low sulfur application method, a ceramic thermal barrier coating overlying the substrate, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.
Claim 24
Dependent Claim
43 words
The method of claim 20, including the additional step, after the step of furnishing and before the step of applying, of providing at least a portion of the surface of the article with an environmental coating that forms an aluminum-oxide scale upon heating.
Claim 25
Dependent Claim
24 words
The method of claim 21, wherein the step of providing includes the step of depositing an aluminum-oxide scale on the surface of the article.
Claim 26
Dependent Claim
24 words
The method of claim 21, wherein the step of providing includes the step of depositing an aluminum-rich overcoating onto the surface of the substrate.
Claim 27
Dependent Claim
9 words
An article prepared by the process of claim 20.
References Cited (Backward Citations)
US3544348A
Cited
US3581491A
Cited
US3853540A
Cited
US3928026A
Cited
US4142023A
Cited
US4152223A
Cited
US4530720A
Cited
US4626408A
Cited
US4895201A
Cited
US5262245A
Cited
US5034284A
Cited
US5346563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-07-23 | 2000-01-22 | 2000-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-07-23 | 2004-01-22 | 2004-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-07-23 | 2008-01-22 | 2008-07-23 | $7700.00 | Window Closed / Lapsed |