Stabilisation du monocarbure d'uranium et production de carbure monophase: Volume 1 & 2

To obtain single-phase uranium carbide, uranium Carbide with 3.5 to 8 wt. % of carbon was subjected to are melting in a mixed argon nitrogen atmosphere and a mixed argon-air atmosphere. The carbon and nitrogen contents of the final product were checked and found to depend on the partial pressure of nitrogen and oxygen. As a result of melting in an argon-nitrogen atmosphere some nitrogen goes into the carbide. The carbon content aIso increases as a result
of contamination by the graphite electrode. By this process a substoichiometric
carbide could be made stoichiometric. The melting in a mixed argon-nitrogen-oxygen atmosphere produces a decrease in the carbon content as a result of a reaction between the carbides and the oxygen, The nitrogen content also increases. The nitrogen reacts with the free uranium to form uranium mononitride, which passes in solution into the uranium monocarbide, Thus, the melting of uranium carbides in the presence of oxygen and nitrogen yields a single-phase uranium carbon nitride.