A metal alloy fuel is being developed as a next generation fuel for light water reactor (LWR) systems. In order to advance the evolution of fuel technology Texas A&M University is evaluating the potential use of this fuel in current generation LWR cores in collaboration with Lightbridge Corporation (McLean, VA, USA).The goal of this project is to evaluate the irradiation performance of a novel uranium-zirconium alloy fuel form with a cruciform geometry. The proposed work will generate information necessary to perform a quantitative comparison of the fuel performance characteristics of this fuel with those of the current oxide fuel used in the commercial industry. Although the new alloy fuel is designed for LWR application, the knowledge and data generated in this work will contribute to the body of knowledge concerning metal fuels that has previously centered on fast reactor systems. It is therefore noteworthy that the data from the proposed irradiation experiments may be beneficial DOE-NE programs that are promulgating advanced fuels for LWR sustainability and fast reactor designs.The focus of this proposal is a Lightbridge Corporation developed metallic fuel with enhanced in-reactor performance, improved fuel reliability and increased safety margin compared to conventional UO2 fuels. The proposed project has the following primary objectives:1. Pre-irradiation characterization of fuel specimens to obtain baseline microstructural information and fuel property measurements.2. Capsule irradiation of fuel specimens in ATR to the selected burnup.3. Post-irradiation examination of the fuel to quantify microstructural and thermophysical property changes.The results of this work will advance fundamental understanding of the irradiation performance of the metal fuel form, including fuel swelling, constituent redistribution, fission gas retention and thermal conductivity. While outside the scope of the current proposal, positive results from the proposed capsule irradiation tests could serve as a stepping stone for subsequent loop irradiation tests that Texas A&M University and Lightbridge anticipate as part of a future proposal.

Metal fuels have been extensively studied by the U.S. DOE for fast reactor systems such as the Experimental Breeder Reactor-II and the Integral Fast Reactor. The proposed work will both build upon and benefit from the body of knowledge generated during that research. Further, the novel fuel design has the potential to meet the needs of higher burnup and superior performance for the DOE program on Light Water Reactor Sustainability (LWRS).