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US5024710A
Expired / Lapsed
US
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Process of applying a specular surface finish to a carbon-carbon substrate
Assignee: Aerospace Corp
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Filing: 1990-03-09
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Granted: 1991-06-18
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Expires: 2010-03-09
Abstract
Abstract A novel method is disclosed for producing specular surfaces, composed of pure carbon, on carbon-carbon composites of arbitrary weave configuration. The method utilizes a thin sheet of fine grained polycrystalline graphite as a stress-isolating interlayer between the composite substrate and the specular surface layer. The interlayer is bonded to the carbon-carbon substrate with a high char yield carbonizable adhesive. An outer layer of glassy carbon is then applied using a high char yield resin solution or (lacquer). The resulting assembly is then carbonized to convert all uncarbonized polymer to carbon. The interlayer prevents the propagation of the substrate carbon-carbon composite's crack structure to the glossy carbonized polymer surface thus formed, resulting in a high degree of specularity and zero gas permeability.
Inventors
- 👤 Patrick M. Sheaffer
- 👤 James A. Noblet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:33
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/83; C04B41/45; C04B41/52; C04B41/80; C04B41/81; C04B41/89
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
160 words
The process of applying a specular surface to a carbon-carbon (CC) composite substrate having an inherent microcrack network, said process including: a. coating the CC composite substrate with a high char yield organic polymer resin lacquer and allowing the lacquer vehicle to evaporate; b. providing a conforming interlayer for the coated CC substrate, said interlayer being composed of a polycrystalline graphite (PCG) having a tough, fine-grain structure; c. coating the interlayer with a high char yield organic polymer resin lacquer and allowing the lacquer vehicle to evaporate; d. abutting the coated surfaces of the CC composite substrate and the interlayer under pressure and curing the polymer coatings, followed by pyrolysis to provide a carbonaceous mechanical bond between the CC composite substrate and the interlayer; e. applying a high char yield organic resin lacquer coating to an exposed surface of the interlayer, drying the coating and pyrolyzing the residual organic resin to form a glassy carbon specular surface on the interlayer.
Claim 2
Dependent Claim
160 words
The process of applying a specular surface to a carbon-carbon (CC) composite substrate having an inherent microcrack network, said process including: a. coating the CC composite substrate with a high char yield organic polymer resin lacquer and allowing the lacquer vehicle to evaporate; b. providing a conforming interlayer for the coated CC substrate, said interlayer being composed of a polycrystalline graphite (PCG) having a tough, fine-grain structure; c. coating the interlayer with a high char yield organic polymer resin lacquer and allowing the lacquer vehicle to evaporate; d. abutting the coated surfaces of the CC composite substrate and the interlayer under pressure and curing the polymer coatings, followed by pyrolysis to provide a carbonaceous mechanical bond between the CC composite substrate and the interlayer; e. applying a high char yield organic resin lacquer coating to an exposed surface of the interlayer, drying the coating and pyrolyzing the residual organic resin to form a glassy carbon specular surface on the interlayer.
Claim 3
Dependent Claim
38 words
The process of claim 1 in which the organic resin in the lacquer that is applied as a bond between the CC composite substrate and the interlayer and that is used to form the specular surface is polyarylacetylene.
Claim 4
Dependent Claim
46 words
The process of claim 1 in which the high char yield resin forming a bond between the CC composite substrate and the interlayer is heated at a slow rate of about 20° C. per hour to prevent blistering of the bond by trapped gases of pyrolysis.
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) | 1994-06-17 | 1994-12-17 | 1995-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-17 | 1998-12-17 | 1999-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-17 | 2002-12-17 | 2003-06-18 | $7700.00 | Window Closed / Lapsed |