Dawn E. Janney

Report to the DOE on the “Crud II” project

This report documents SEM, TEM, and chemical analyses from crud samples from a commercially operating reactor.

Experimentally Known Properties of U-10Zr Alloys: A Critical Review

Abstract More than 14 000 U-10Zr fuel rods (alloys of U with 10 wt% Zr) were irradiated in the Experimental Breeder Reactor II and Fast Flux Test Facility, with some irradiated to burnups of almost 20 at. %. However, very little information about properties of unirradiated U-10Zr alloys is available. These data are needed to help with interpretation of data from irradiated materials, to develop and validate phase diagrams and models of U-Zr and more complex systems, to inform and validate fuel performance codes, to design fuels for future fast reactors, and to guide future experimental investigations to fill in crucial gaps in knowledge. This paper provides a summary and critical review of the available experimental data on phases and phase diagrams, electrical properties, thermal expansion, thermal conductivity, heat capacity, mechanical properties, vapor pressures, and thermodynamic properties of unirradiated U-10Zr alloys. Many of the reported values were published before approximately 1970 and are available only in obscure reports. This critical review concludes by identifying areas where additional experimental measurements are particularly necessary and makes recommendations on prioritization of new measurements with a view to the emerging needs associated with the mechanistic modeling of nuclear fuels and their performance.