Patent US4676994A successfully refreshed from Google Patents.
US4676994A
Expired / Lapsed
US
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Adherent ceramic coatings
Assignee: Messer LLC
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Filing: 1985-03-28
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Granted: 1987-06-30
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Expires: 2005-03-28
Abstract
Abstract A method for depositing a coating of a dense ceramic material is disclosed. The coating may be an oxide or other refractory ceramic material. A ceramic starting material is melted and refined by heating with an electron beam in vacuum. The refined material is evaporated and deposited on a heated substrate to form a dense ceramic coating. In particular, a durable ceramic thermal barrier coating on a superalloy turbine part may be formed by coating the part with a metal layer which is oxidized to form alumina and depositing a dense ceramic layer followed by an overcoating of a columnar ceramic material.
Inventors
- 👤 Richard E. Demaray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:31
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/02; C23C14/028; C23C14/024; C23C14/025; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12542; Y10T428/12549; Y10T428/12583; Y10T428/1259; Y10T428/12611; Y10T428/12618; Y10T428/12771; Y10T428/12861; Y10T428/12931
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
87 words
A method of depositing a ceramic coating on a substrate having a ceramic surface, comprising: melting and refining a first ceramic material by heating with an electron beam in vacuum to form a substoichiometric ceramic liquid, heating the substrate in vacuum to a temperature greater than about 900° C., evaporating the refined ceramic liquid in vacuum, and exposing the heated substrate to the substoichio metric vapor to deposit a dense ceramic layer on the substrate, and depositing a layer of columnar ceramic on the dense ceramic layer.
Claim 2
Independent Claim
87 words
A method of depositing a ceramic coating on a substrate having a ceramic surface, comprising: melting and refining a first ceramic material by heating with an electron beam in vacuum to form a substoichiometric ceramic liquid, heating the substrate in vacuum to a temperature greater than about 900° C., evaporating the refined ceramic liquid in vacuum, and exposing the heated substrate to the substoichio metric vapor to deposit a dense ceramic layer on the substrate, and depositing a layer of columnar ceramic on the dense ceramic layer.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein the dense ceramic layer is deposited in a vacuum at a pressure of 10 -4 torr or less.
Claim 4
Dependent Claim
18 words
The method of claim 1 further comprising continuously moving the substrate while it is exposed to the vapor.
Claim 5
Dependent Claim
26 words
The method of claim 3 wherein the substrate is rotated at a rate greater than 10 revolutions per minute while it is exposed to the vapor.
Claim 6
Dependent Claim
27 words
The method of claim 1 wherein the dense ceramic layer has a density greater than about 94% of the maximum theoretical density of the first ceramic material.
Claim 7
Dependent Claim
28 words
The method of claim 1 wherein the thickness of the dense ceramic layer is 2 to 10 times the RMS average roughness of the surface to be coated.
Claim 8
Dependent Claim
21 words
The method of claim 6 wherein the RMS average roughness of the surface to be coated in 250 nm or less.
Claim 9
Dependent Claim
32 words
The method of claim 1 wherein the substrate surface to be coated is curved and the thickness of the dense ceramic layer is less than 10 times the minimum radius of curvature.
Claim 10
Dependent Claim
16 words
The method of claim 8 wherein the minimum radius of curvature is 1.2 mm or less.
Claim 11
Dependent Claim
28 words
The method of claim 8 wherein the thickness of the dense ceramic layer is 2 to 10 times the RMS average roughness of the surface to be coated.
Claim 12
Dependent Claim
38 words
A substrate coated with a layer of dense ceramic material by the method of claim 1 wherein the initial average dimension perpendicular to the growth direction of grains in the dense ceramic layer is less than 100 nm.
Claim 13
Independent Claim
97 words
A method of depositing a dense ceramic coating on a metal article coated with a layer of an alumina forming material which has been oxidized, comprising: melting and refining a first ceramic material by heating with an electron beam in vacuum to form a substoichiometric ceramic liquid, heating the substrate in vaccum to a temperature greater than about 900° C., evaporating the refined ceramic liquid in vacuum, and exposing the heated substrate to the substoichiometric vapor to deposit a dense ceramic layer on the substrate, and depositing a layer of columnar ceramic on the dense ceramic layer.
Claim 14
Independent Claim
97 words
A method of depositing a dense ceramic coating on a metal article coated with a layer of an alumina forming material which has been oxidized, comprising: melting and refining a first ceramic material by heating with an electron beam in vacuum to form a substoichiometric ceramic liquid, heating the substrate in vaccum to a temperature greater than about 900° C., evaporating the refined ceramic liquid in vacuum, and exposing the heated substrate to the substoichiometric vapor to deposit a dense ceramic layer on the substrate, and depositing a layer of columnar ceramic on the dense ceramic layer.
Claim 15
Dependent Claim
25 words
The method of claim 12, wherein the columnar ceramic layer is deposited by electron-beam heated evaporation of second ceramic material in the presence of oxygen.
Claim 16
Dependent Claim
20 words
The method of claim 13 wherein the alumina forming material is MCrAlY where M is Ni, Co, NiCo, or Fe.
Claim 17
Dependent Claim
37 words
The method of claim 14 wherein the thickness of the dense ceramic layer is between 500 nm and 10 mm, and the pressure during the deposition of the first ceramic material is less than 2×10 -5 torr.
Claim 18
Dependent Claim
39 words
The method of claim 15 wherein the partial pressure of oxygen during the deposition of the columnar ceramic layer is between 0.5 and 2 millitorr and the partial pressure of other gases is less than 10% the total pressure.
Claim 19
Dependent Claim
16 words
A substrate coated with a layer of dense ceramic material by the method of claim 16.
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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) | 1990-06-29 | 1990-12-29 | 1991-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-29 | 1994-12-29 | 1995-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-29 | 1998-12-29 | 1999-06-30 | $7700.00 | Window Closed / Lapsed |