Non-Destructive Characterization of UO 2+ x Nuclear Fuels

Abstract

This article describes the effect of fabrication conditions on as-sintered microstructures of various stoichiometric ratios of uranium dioxide, UO 2 + x , with the aim of enhancing the understanding of the fabrication process and developing and validating a predictive microstructure-based model for fuel performance. We demonstrate the ability of novel, non-destructive methods such as near-field high-energy X-ray diffraction microscopy (nf-HEDM) and micro-computed tomography (μ-CT) to probe bulk samples of high-Z materials by non-destructively characterizing three samples: UO 2.00 , UO 2.11 , and UO 2.16 , which were sintered at 1450°C for 4 hours. The measured 3D microstructures revealed that grain size and porosity were influenced by deviation from stoichiometry.