US3755243A
Expired / Lapsed
US
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Dense graphite structures
Assignee: RTX Corp
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Filing: 1971-03-25
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Granted: 1973-08-28
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Expires: 1991-03-25
Abstract
Abstract This disclosure describes a graphite composition and a fabrication procedure for producing coolant and/or support plates for acid fuel cells. The composition consists of a graphite powder sized principally in the 50 to 150 micron range with about seven percent of the graphite powder in the range below 50 microns. The process involves a controlled low-pressure heating step and an intermediate temperature full-pressure molding operation. Homogeneous graphite structures of high density with improved structural, thermal, and electrical properties can be provided in a variety of extremely intricate shapes by molding.
Inventors
- 👤 R Emanuelson
- 👤 W Luoma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:28
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C04B35/528; C04B35/532; H; H01; H01M; H01M8/00; H01M8/02; H01M8/0202; H01M8/0204; H01M8/0213; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
97 words
A dense graphite structure as defined in claim 1, wherein the graphite particles have a particle size distribution in accordance with the following limits: 46 to 66 percent of the particles are in the 80 to 160 micron range, 35 to 60 percent of the particles are in the 60 to 100 micron range, 20 to 40 percent of the particles are in the 50 to 80 micron range, eight to 18 percent of the particles are in the 40 to 60 micron range, and three to 12 percent of the particles are less than 50 microns.
Claim 2
Dependent Claim
88 words
A dense graphite structure as defined in claim 1, wherein the graphite particles h;ve a particle size distribution substantially in accordance with the following limits: 56 perCent of the particles are in the 80 to 100 micron range, 47 percent of the particles are in the 60 to 100 micron range, 30 percent of the particles are in the 50 to 80 micron range, 13 percent of the particles are in the 40 to 60 micron range, and seven percent of the particles are less than 50 microns.
Claim 3
Dependent Claim
72 words
A dense graphite structure as defined in claim 1, wherein the structure has substantially the following physical characteristics: a density of about 2.0 gm/cc, a compressive strength of about 15,000 lb./in.2, an electrical resistivity of about 4.3 X 103 ohm/cm., a thermal conductivity of about 32.5 BTU/hr./ ft/*F when measured in a direction perpendicular to pressing and a thermal conductivity of about 17 BTU/hr./ft/*F when measured in a direction parallel to pressing.
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) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |