Patent US4425407A successfully refreshed from Google Patents.
US4425407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
CVD SiC pretreatment for carbon-carbon composites
Assignee: RTX Corp
•
Filing: 1982-06-24
•
Granted: 1984-01-10
•
Expires: 2002-06-24
Abstract
Abstract Carbon-carbon composites are prepared to receive a subsequent protective coating by having a thin coating (0.1 to 5 mils) of chemically vapor deposited (CVD) SiC applied to its surface. The SiC layer improves the performance of subsequent protective coatings (especially pack produced SiC conversion coatings), especially in the case of carbon-carbon composites having a negative coefficient of thermal expansion.
Inventors
- 👤 Francis S. Galasso
- 👤 Richard D. Veltri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:11
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/83; C04B41/45; C04B41/50; C04B41/5053; C04B41/5057; C04B41/5059; C04B41/80; C04B41/81; C04B41/85; C04B41/87; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T428/292; Y10T428/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
66 words
A carbon-carbon composite article having carbon fibers surrounded by a carbon matrix characterized in that diffusion of silicon within the fibers occurs at a different rate than does the diffusion of silicon within the matrix, said article being adapted to receive a subsequent uniform protective coating, said article comprising: carbon-carbon composite substrate having on its outer surface, a 0.1 to 5 mil layer of CVD SiC.
Claim 2
Dependent Claim
66 words
A carbon-carbon composite article having carbon fibers surrounded by a carbon matrix characterized in that diffusion of silicon within the fibers occurs at a different rate than does the diffusion of silicon within the matrix, said article being adapted to receive a subsequent uniform protective coating, said article comprising: carbon-carbon composite substrate having on its outer surface, a 0.1 to 5 mil layer of CVD SiC.
Claim 3
Dependent Claim
20 words
A carbon-carbon composite as in claim 1 having a coefficient of thermal expansion less than about 0.3×10 -6 cm/cm° C.
Claim 4
Independent Claim
45 words
A method of preparing a carbon-carbon composite article to receive a protective coating which comprises applying a 0.1 to 5 mil layer of CVD SiC, so that compositional and crystallographic variations in the carbon-carbon article are masked and do not affect the subsequent protective coating.
Claim 5
Independent Claim
45 words
A method of preparing a carbon-carbon composite article to receive a protective coating which comprises applying a 0.1 to 5 mil layer of CVD SiC, so that compositional and crystallographic variations in the carbon-carbon article are masked and do not affect the subsequent protective coating.
Claim 6
Dependent Claim
47 words
In a process for coating a carbon-carbon surface to resist attack at elevated temperatures, the improvement which comprises: applying a 0.1-1.5 mil layer of CVD SiC to the carbon-carbon surface prior to applying a protective coating; whereby the compositional and crystallographic variations in the surface are masked.
Claim 7
Dependent Claim
47 words
In a process for coating a carbon-carbon surface to resist attack at elevated temperatures, the improvement which comprises: applying a 0.1-1.5 mil layer of CVD SiC to the carbon-carbon surface prior to applying a protective coating; whereby the compositional and crystallographic variations in the surface are masked.
Claim 8
Independent Claim
51 words
A method for masking and minimizing the effects of compositional and crystallographic variations in the surface of a carbon-carbon composite material, so that these variations do not significantly affect the protective capabilities of a subsequently applied coating; which comprises applying a 0.1-1.5 mil layer of CVD SiC to the carbon-carbon surface.
Claim 9
Independent Claim
51 words
A method for masking and minimizing the effects of compositional and crystallographic variations in the surface of a carbon-carbon composite material, so that these variations do not significantly affect the protective capabilities of a subsequently applied coating; which comprises applying a 0.1-1.5 mil layer of CVD SiC to the carbon-carbon surface.
References Cited (Backward Citations)
US2992127A
Cited
US3095316A
Cited
US3226194A
Cited
US3406044A
Cited
US3853586A
Cited
US3935034A
Cited
US4142008A
Cited
US3925577A
Cited
US3969130A
Cited
US4029844A
Cited
US3980105A
Cited
US4241104A
Cited
US4214037A
Cited
GB2081695A
Cited
US4340636A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-09 | 1987-07-11 | 1988-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-09 | 1991-07-11 | 1992-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-09 | 1995-07-11 | 1996-01-10 | $7700.00 | Window Closed / Lapsed |