b'Fabrication of high-density fuels at the miniature scale has been demonstrated, allowing rapid irradiation testing and characterization of emerging accident tolerant nuclear fuel materials using a separate effects testing approach.testing. Efforts at Los Alamos Nationalrelationships and the thermophysical Laboratory (LANL) have focusedcharacteristics of U 3 Si 2at peak on the synthesis and fabricationoperating temperatures is necessary (via powder metallography routes)for potential implementation in the of high-density uranium silicidecurrent nuclear energy infrastructure. (U 3 Si 2 ) test specimens to MiniFuelThis can be achieved by studying specifications. novel fuel forms (such as U 3 Si 2 ) at the Project Descriptions: MiniFuel scale (~3 mm diameter, less The primary objective of this projectthan 300 m thickness). The reduced are fabrication and preliminaryradioactivity and bulk specimen size thermophysical property assessmentsassociated with the MiniFuel concept of high-density U 3 Si 2MiniFuel testaids in addressing key challenges specimens. U 3 Si 2has been proposedassociated with rapid postirradiation as a candidate material as it offerstesting and accelerated measurements enhanced thermal conductivity (thisof material properties relevant toreduces the propensity for thermalfuel performance.stress failures) and a uranium densityFabrication of MiniFuel U 3 Si 2that is higher than conventionalspecimens was carried out at the Fuels uranium dioxide (UO 2 ) fuels, whichResearch Laboratory (FRL) at LANL can enhance the economic viabilityusing standard powder metallography of nuclear power plant operation.techniques, with the aim of achieving Nevertheless, full elucidation ofsample density >90% theoretical postirradiation structure-property 2019|AFC ACCOMPLISHMENTS 71'