Characterization of 60U-20Pu-3Am-2Np-15Zr alloys with 1.5wt% rare earth elements

Metallic fuel alloys consisting of uranium, plutonium and zirconium with minor additions of americium and neptunium are under evaluation for potential use to transmute long-lived transuranic actinide isotopes in fast reactors. The current irradiation design includes minor additions of rare earth elements to simulate expected fission product carry-over from the electrochemical molten salt reprocessing technique, along with the recycled U, Pu, Am, and Np. The metal fuel alloys have been fabricated by an arc casting technique. The as-cast fuel alloys have been investigated for their thermal properties, specifically, heat capacity, enthalpies of transition, transition temperatures, and room temperature phase characteristics. Results and observations related to these characteristics for two of the "fresh "fuel alloys are provided in this presentation:60U-20Pu-3Am-2Np-15Zr (Al) and 58.5U-20Pu-3Am-2Np-15Zr-1.5RE (A3) (nominal weight percentages; RE denotes rare earth alloy of cerium, lanthanum, praseodymium and neodymium). Impacts associated with the minor rare earth additions on the base alloy are also provided in this presentation.