US4180428A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making hot-pressed fiber-reinforced carbide-graphite composite
Assignee: United States Department of Energy
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Filing: 1978-06-23
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Granted: 1979-12-25
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Expires: 1998-06-23
Abstract
Abstract A method for the chemical vapor deposition of a uniform coating of tantalum metal on fibers of a woven graphite cloth is described. Several layers of the coated cloth are hot pressed to produce a tantalum carbide-graphite composite having a uniformly dispersed, fine grained tantalum carbide in graphite with compositions in the range of 15 to 40 volume percent tantalum carbide.
Inventors
- 👤 Robert E. Riley
- 👤 Terry C. Wallace Sr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:07
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/06; C23C16/08; C23C16/14; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C04B35/622; C04B35/64; C04B35/645; C04B35/71; C04B35/78; C04B35/80
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
143 words
An improved method for making a hot pressed, fiber-reinforced carbide-graphite composite being 15 to 40 volume percent Ta carbide, said improvement comprising: (a) contacting multiple layers of filaments of a graphite cloth with a gas having the following range of composition by volume percent (I) 0.5 to 5.0-tantalum pentachloride (II) 0 to 25-hydrogen chloride (gas) (III) 50 to 95-hydrogen and (IV) 0 to 50-inert gas, (b) the said gas reacting with the filaments to form a coating, said coating being formed in a temperature range of 650° to 900° C., (c) at a pressure of 0.01 to 0.3 atmosphere, (d) the coating time dependent on the amount of Ta carbide formed in the composite, and then, (e) hot pressing multiple layers of filaments at a temperature of about 3000° C., a pressure of about 3000 psi, for a period of about 10 minutes.
Claim 2
Dependent Claim
143 words
An improved method for making a hot pressed, fiber-reinforced carbide-graphite composite being 15 to 40 volume percent Ta carbide, said improvement comprising: (a) contacting multiple layers of filaments of a graphite cloth with a gas having the following range of composition by volume percent (I) 0.5 to 5.0-tantalum pentachloride (II) 0 to 25-hydrogen chloride (gas) (III) 50 to 95-hydrogen and (IV) 0 to 50-inert gas, (b) the said gas reacting with the filaments to form a coating, said coating being formed in a temperature range of 650° to 900° C., (c) at a pressure of 0.01 to 0.3 atmosphere, (d) the coating time dependent on the amount of Ta carbide formed in the composite, and then, (e) hot pressing multiple layers of filaments at a temperature of about 3000° C., a pressure of about 3000 psi, for a period of about 10 minutes.
Claim 3
Dependent Claim
47 words
The method of claim 1 in which the said gas has a composition of: (I) 4 volume percent tantalum pentachloride (II) 4 volume percent hydrogen chloride (III) 82 volume percent hydrogen gas (IV) 10 volume percent argon, a pressure of 0.16 atmosphere, and temperature of 800° C.
Claim 4
Dependent Claim
24 words
The method of claim 2 in which the coating time is approximately 30 minutes, and the TaC is 15 volume percent of the composite.
Claim 5
Dependent Claim
24 words
The method of claim 2 in which the coating time is approximately 50 minutes and the TaC is 25 volume percent of the composite.
Claim 6
Dependent Claim
24 words
The method of claim 2 in which the coating time is approximately 80 minutes, and the TaC is 40 volume percent of the composite.
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) | 1982-12-24 | 1983-06-25 | 1983-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-24 | 1987-06-25 | 1987-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-24 | 1991-06-25 | 1991-12-25 | $7700.00 | Window Closed / Lapsed |