US3953556A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing uranium nitride or uranium carbonitride bodies
Assignee: Energy Research and Development Administration ERDA
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Filing: 1974-05-17
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Granted: 1976-04-27
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Expires: 1994-05-17
Abstract
Abstract Sintered uranium nitride or uranium carbonitride bodies having a controlled final carbon-to-uranium ratio are prepared, in an essentially continuous process, from U 3 O 8 and carbon by varying the weight ratio of carbon to U 3 O 8 in the feed mixture, which is compressed into a green body and sintered in a continuous heating process under various controlled atmospheric conditions to prepare the sintered bodies.
Inventors
- 👤 Harley A. Wilhelm
- 👤 James K. McClusky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:53
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/51; G; G21; G21C; G21C3/00; G21C3/42; G21C3/58; G21C3/62; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
192 words
A method of preparing sintered uranium nitride or uranium carbonitride bodies having controlled final carbon-to-uranium ratio in a single furnace comprising: a. mixing U 3 O 8 with a predetermined amount of carbon to prepare a charge, the weight ratio of carbon to U 3 O 8 in the charge being determined by the formula C = 0.1027 + 0.0428X, where X = atom ratio of carbon with respect to uranium in the final uranium nitride or uranium carbonitride body; b. compacting the charge into a green body; c. heating the green body to about 1000°C. until the U 3 O 8 in the body is reduced to UO 2 ; d. heating the body under reduced pressure to about 1350°C. until the uranium dioxide is converted to UOC or to UOC plus UC; e. heating the body under a flowing atmosphere of nitrogen to about 1750°C. whereby the UOC is nitrided to uranium nitride; and f. heating the body to about 1900°C. under reduced pressure whereby excess nitrogen is removed and the body is sintered, thereby forming a sintered uranium nitride or uranium carbonitride body having a controlled final carbon-to-uranium ratio.
Claim 2
Independent Claim
192 words
A method of preparing sintered uranium nitride or uranium carbonitride bodies having controlled final carbon-to-uranium ratio in a single furnace comprising: a. mixing U 3 O 8 with a predetermined amount of carbon to prepare a charge, the weight ratio of carbon to U 3 O 8 in the charge being determined by the formula C = 0.1027 + 0.0428X, where X = atom ratio of carbon with respect to uranium in the final uranium nitride or uranium carbonitride body; b. compacting the charge into a green body; c. heating the green body to about 1000°C. until the U 3 O 8 in the body is reduced to UO 2 ; d. heating the body under reduced pressure to about 1350°C. until the uranium dioxide is converted to UOC or to UOC plus UC; e. heating the body under a flowing atmosphere of nitrogen to about 1750°C. whereby the UOC is nitrided to uranium nitride; and f. heating the body to about 1900°C. under reduced pressure whereby excess nitrogen is removed and the body is sintered, thereby forming a sintered uranium nitride or uranium carbonitride body having a controlled final carbon-to-uranium ratio.
Claim 3
Dependent Claim
14 words
The process of claim 1 wherein the green body is heated under reduced pressure.
Claim 4
Dependent Claim
15 words
The process of claim 1 wherein the green body is heated in an inert atmosphere.
Claim 5
Dependent Claim
23 words
The process of claim 3 wherein the inert atmosphere is flowing and is selected from the group consisting of nitrogen, argon and helium.
Claim 6
Dependent Claim
31 words
The process of claim 4 wherein the UO 2 body is heated under a pressure of not more than about 1 mm of mercury to from about 1350°C. to about 1550°C.
Claim 7
Dependent Claim
24 words
The process of claim 5 wherein the body of UOC or UOC and UC is further heated to from about 1750°C. to about 1850°C.
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) | 1979-04-27 | 1979-10-27 | 1980-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-27 | 1983-10-27 | 1984-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-27 | 1987-10-27 | 1988-04-27 | $7700.00 | Window Closed / Lapsed |