| Revision as of 14:49, 9 December 2004 editPatrick (talk | contribs)Edit filter managers, Administrators68,523 edits The fissile uranium in nuclear weapons usually contains 85% or more of U-235, though for a crude inefficient weapon 20% is sufficient (or even less, but then the critical mass rapidly increases).← Previous edit | Revision as of 00:25, 10 December 2004 edit undoPatrick (talk | contribs)Edit filter managers, Administrators68,523 edits miscNext edit → | ||
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| '''Enriched uranium''' is ] whose ] content has been increased through the process of ]. Natural uranium consists mostly of the ] ], with about 0.7 percent by weight as U-235 which is the only isotope existing in nature to any appreciable extent that is ] by ]s |
'''Enriched uranium''' is ] whose ] content has been increased through the process of ]. Natural uranium consists mostly of the ] ], with about 0.7 percent by weight as U-235 which is the only isotope existing in nature to any appreciable extent that is ] by ]s. | ||
| '''Highly enriched uranium (HEU)''' |
'''Highly enriched uranium (HEU)''' has a greater than 20% concentration of U-235. | ||
| The fissile uranium in nuclear weapons usually contains 85% or more of U-235, though for a crude inefficient weapon 20% is sufficient (or even less, but then the ] rapidly increases). The presence of too much of the U-238 isotope inhibits the runaway ] that is responsible for the weapon's power. | The fissile uranium in nuclear weapons usually contains 85% or more of U-235, though for a crude inefficient weapon 20% is sufficient (or even less, but then the ] rapidly increases). The presence of too much of the U-238 isotope inhibits the runaway ] that is responsible for the weapon's power. | ||
| HEU is also used in ], where it contains at least 50% U-235, but typically exceeds 90%. | |||
| '''Low-enriched uranium (LEU)''' has a lower than 20% concentration of U-235. | |||
| For use in commercial ]s natural uranium is enriched to 3 to 5 percent U-235. | |||
| During the ] enriched uranium was given the codename oralloy, a shortened version of Oak Ridge alloy, after the plant where the uranium was enriched. The term oralloy is still occasionally used to refer to enriched uranium. The remaining U-238 with extremely low U-235 content is known as ], and is considerably less ] than even natural uranium, though still extremely dense and is useful for ] and armor penetrating weapons. | During the ] enriched uranium was given the codename oralloy, a shortened version of Oak Ridge alloy, after the plant where the uranium was enriched. The term oralloy is still occasionally used to refer to enriched uranium. The remaining U-238 with extremely low U-235 content is known as ], and is considerably less ] than even natural uranium, though still extremely dense and is useful for ] and armor penetrating weapons. | ||
Revision as of 00:25, 10 December 2004
Enriched uranium is uranium whose uranium-235 content has been increased through the process of isotope separation. Natural uranium consists mostly of the U-238 isotope, with about 0.7 percent by weight as U-235 which is the only isotope existing in nature to any appreciable extent that is fissionable by thermal neutrons.
Highly enriched uranium (HEU) has a greater than 20% concentration of U-235.
The fissile uranium in nuclear weapons usually contains 85% or more of U-235, though for a crude inefficient weapon 20% is sufficient (or even less, but then the critical mass rapidly increases). The presence of too much of the U-238 isotope inhibits the runaway nuclear chain reaction that is responsible for the weapon's power.
HEU is also used in nuclear submarine reactors, where it contains at least 50% U-235, but typically exceeds 90%.
Low-enriched uranium (LEU) has a lower than 20% concentration of U-235.
For use in commercial nuclear reactors natural uranium is enriched to 3 to 5 percent U-235.
During the Manhattan Project enriched uranium was given the codename oralloy, a shortened version of Oak Ridge alloy, after the plant where the uranium was enriched. The term oralloy is still occasionally used to refer to enriched uranium. The remaining U-238 with extremely low U-235 content is known as depleted uranium, and is considerably less radioactive than even natural uranium, though still extremely dense and is useful for armor and armor penetrating weapons.
The ability to enrich uranium is one of the key factors in nuclear weapons proliferation.
Separative work is expressed in SWU (separative work unit), kg SW, or kg UTA (from the German Urantrennarbeit ), possibly with a prefix:
- 1 SWU = 1 kg SW = 1 kg UTA
- 1 kSWU = 1 tSW = 1 t UTA
- 1 MSWU = 1 ktSW = 1 kt UTA
See the external link for the definition.
For information on how uranium is enriched see isotope separation.
External link
- Uranium enrichment (pdf)