Abstract Scope |
Uranium nitride has excellent thermal conductivity, high uranium volume fraction, and compatibility with potential nuclear reactor liquid metal coolants, making it of interest for a Gen IV lead-cooled nuclear reactor design. The dearth of knowledge about UN fuel, however, is a hindrance to its eventual adoption, including its behavior with the many different fission products that are generated, including rare earth and alkaline earth elements. Understanding how they interact with the UN fuel is important for predicting their long-term stability, thermal expansion, thermal conductivity, mechanical behavior, and fuel-cladding interactions. To help address the issue, a thermodynamic database has been developed to simulate (U,Pu)N-fission product-minor actinide. The database contains 18 elements, including 12 mononitride components and models of their solid solution behavior. The database is being used in thermodynamic equilibrium calculations to predict phase equilibria and chemical behavior, particularly at high burnup. |