US4022660A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coated particles
Assignee: General Atomics Corp
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Filing: 1974-03-14
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Granted: 1977-05-10
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Expires: 1994-03-14
Abstract
Abstract A nuclear fuel particle wherein a core, up to about 250 microns in diameter, of a normally solid fissionable material is completely encased in a shell having at least two concentric layers. A yielding of carbonaceous material about 5 to about 50 microns thick is disposed inward of a layer of substantially impermeable refractory material, e.g., pyrocarbon, up to about 100 microns thick. Examples of the yielding layer include carbonized synthetic polymer resins and sooty pyrocarbon.
Inventors
- 👤 James R. Johnson
- 👤 Harold G. Sowman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:54
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/42; G21C3/58; G21C3/62; G21C3/626; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
89 words
A nuclear fuel particle which comprises a central core of normally solid fissionable material in the form of a spherule between about 10 microns and about 250 microns in diameter encased in a shell having at least two concentric layers, a yielding inner layer of said shell being composed of carbonaceous material and having a thickness between about 5 and about 50 microns, and an outer layer of said shell being composed of a substantially impermeable refractory material and having a thickness between about 10 and about 100 microns.
Claim 2
Dependent Claim
89 words
A nuclear fuel particle which comprises a central core of normally solid fissionable material in the form of a spherule between about 10 microns and about 250 microns in diameter encased in a shell having at least two concentric layers, a yielding inner layer of said shell being composed of carbonaceous material and having a thickness between about 5 and about 50 microns, and an outer layer of said shell being composed of a substantially impermeable refractory material and having a thickness between about 10 and about 100 microns.
Claim 3
Dependent Claim
17 words
A nuclear fuel particle in accordance with claim 1 wherein said outer layer is formed of pyrocarbon.
Claim 4
Dependent Claim
18 words
A nuclear fuel particle in accordance with claim 1 wherein said yielding inner layer is formed of pyrocarbon.
Claim 5
Dependent Claim
17 words
A nuclear fuel particle in accordance with claim 1 wherein said yielding inner layer is sooty pyrocarbon.
Claim 6
Dependent Claim
22 words
A nuclear fuel particle in accordance with claim 1 wherein said inner layer is pyrocarbon having a density less than 1.8 g./cc.
Claim 7
Dependent Claim
23 words
A nuclear fuel particle in accordance with claim 5 wherein said pyrocarbon has a density between about 1.4 g./cc. and about 1.6 g./cc.
Claim 8
Dependent Claim
23 words
A nuclear fuel particle in accordance with claim 2 wherein said inner layer is sooty pyrocarbon having a density of about 1.4 g./cc.
Claim 9
Dependent Claim
22 words
A nuclear fuel particle in accordance with claim 7 wherein said outer layer has a density of at least about 2 g./cc.
References Cited (Backward Citations)
FR1252507A
Cited
US3231408A
Cited
US3228848A
Cited
US3166614A
Cited
US3121047A
Cited
US3291696A
Cited
US3335063A
Cited
US3488409A
Cited
US3799790A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-09 | 1980-11-08 | 1981-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-09 | 1984-11-08 | 1985-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-09 | 1988-11-08 | 1989-05-10 | $7700.00 | Window Closed / Lapsed |