uranium dioxide
Quick Summary
Uranium dioxide (UO2) is a chemical compound of uranium and oxygen. It is a brown to black crystalline powder that can be formed by heating uranium trioxide or tri-uranium oct-oxide in hydrogen or carbon monoxide. Historically, it was used in gas mantles and ceramic glazes.1
Uranium dioxide is also the form in which uranium is found in primary uranium minerals like uraninite and pitchblende. These minerals can have a composition ranging from UO2 to UO2.67 due to oxidation.2
In modern applications, uranium dioxide is a key component in nuclear reactor fuel. Pellets made of low-enrichment UO2 are universally used in commercial light-water reactors for electricity generation. The process involves blending enriched and natural or depleted UO2 powders, compacting them, and sintering at high temperatures.2
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nuclear reactorFuel types…consisting of pellets of sintered uranium dioxide loaded into cladding tubes of zirconium alloy or some other advanced cladding material. The tubes, called pins or rods, measure approximately 1 cm (less than half an inch) in diameter and roughly 3 to 4 metres (10 to 13 feet) in length. The…
Read More…consisting of pellets of sintered uranium dioxide loaded into cladding tubes of zirconium alloy or some other advanced cladding material. The tubes, called pins or rods, measure approximately 1 cm (less than half an inch) in diameter and roughly 3 to 4 metres (10 to 13 feet) in length. The…
Read More- nuclear reactorFabrication
…prepared for the LWR is uranium dioxide. Produced in the form of a ceramic powder, this compound is ground to a very fine flourlike consistency and inserted into a die, where it is pressed into a pellet shape—in the case of some LWR fuels, approximately 6 mm in diameter and…
Read More…prepared for the LWR is uranium dioxide. Produced in the form of a ceramic powder, this compound is ground to a very fine flourlike consistency and inserted into a die, where it is pressed into a pellet shape—in the case of some LWR fuels, approximately 6 mm in diameter and…
Read More - nuclear ceramicsNuclear fuel
Urania (uranium dioxide, UO2) and plutonia (plutonium dioxide, PuO2) have unique features that qualify them for nuclear fuel applications. First, they are extremely refractory: for instance, the melting point of UO2 is in excess of 2,800° C (5,100° F). Second, the open crystal structure of oxide…
Read MoreUrania (uranium dioxide, UO2) and plutonia (plutonium dioxide, PuO2) have unique features that qualify them for nuclear fuel applications. First, they are extremely refractory: for instance, the melting point of UO2 is in excess of 2,800° C (5,100° F). Second, the open crystal structure of oxide…
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