Uranium Carbide

Uranium Carbide

Uranium carbide is a hard, refractory ceramic substance. It is a chemical compound that contains uranium and carbon. It has the chemical formula UC and is a ceramic substance with a high melting point and good thermal conductivity. It normally comprises uranium and carbon in a 1:1 ratio (UC), but other ratios like UC₂ and UC₃ also exist.

Uranium carbide, like uranium dioxide and other uranium compounds, can be used as nuclear fuel in nuclear reactors, typically in the form of pellets or tablets. Uranium carbide fuel was utilized in the final designs of nuclear thermal rockets.

Uranium carbide pellets are used as fuel kernels for the US version of pebble bed reactors; the German version uses uranium dioxide instead. As nuclear fuel, uranium carbide can be used either on its own, or mixed with plutonium carbide (PuC and Pu2C3). The mixture is also labeled as uranium-plutonium carbide ( (U,Pu)C ).


UC has a very high melting point, exceeding 2700°C (around 4900°F). It exhibits excellent thermal conductivity, making it useful in applications where heat transfer is important. UC is resistant to radiation damage, which makes it suitable for use in nuclear reactors.

  • Chemical formula: UC
  • Molar mass: 250.04 g/mol
  • Density: 13.63 g/cm3
  • Melting point: 2,350 °C (4,260 °F; 2,620 K)
  • Crystal structure: cubic, cF8


  • Nuclear Fuel: It has been studied as a potential nuclear fuel due to its high uranium content and ability to withstand high temperatures and neutron flux.
  • Reactor Core Material: It can be used as a material for the core of nuclear reactors, where it provides both structural integrity and acts as a fuel source.
  • Space Applications: UC has been considered for use in space reactors due to its high energy density and stability under extreme conditions.

Safety Considerations

Uranium carbide can be produced by direct reaction of uranium with graphite or carbon at high temperatures. Like all uranium compounds, UC requires careful handling due to its radioactive nature and potential health hazards associated with uranium exposure.