Abstract
Uranium-molybdenum (U-Mo) is a metallic fuel studied for decades for use in research and test reactors to replace the currently used highly enriched uranium (HEU) with low enriched uranium (LEU). As part of the Material Management and Minimization (M3) program, all civilian sources of HEU must be replaced with materials enriched to less than 20% 235U. The combined effort of computational and experimental work is required to make this goal a reality. Herein, the current gaps in knowledge and empirical data necessary for computational model improvement are highlighted, collected, and analyzed. To complement this data collection, an experiment measuring the elastic modulus of U-Mo is designed using the Resonant Ultrasonic Spectroscopy Laser (RUSL)measurement technique, and the results are predicted. Based on a novel use of molecular dynamics (MD) calculated radiation diffusion and the theory of a critical fission rate where phase reversion occurs, the change in the current phases in U-Mo will happen in the ongoing Transient Reactor Test Facility (TREAT) experiment. This experiment will relate changes in the material elastic modulus to crystallographic phase change and inform computational methods by providing unique data to these studies.