UF6 is an intermediate product used in nuclear fuel fabrication. It is brought to the gaseous state so that the uranium can be isotopically separated and enriched.

Chemical element with the atomic number 92 and symbol U with three natural isotopes: uranium 234, uranium 235 and uranium 238. Uranium 235 is the only naturally occurring fissile nuclide, a property that explains its use as a source of energy.

The uranium contained in nuclear fuel must be enriched in fissile uranium 235. In enrichment by gaseous diffusion, the uranium is first converted into a gas called "uranium hexafluoride", or UF6.