Irradiation and storage effects on nuclear fuel Young’s modulus characterized by high frequency acoustic microscopy

International audienc

Scanning acoustic microscope for mechanical characterization and density estimation of irradiated nuclear fuel

International audienc

A semi-empirical model for the formation and depletion of the high burnup structure in UO2

In the rim zone of UO2 nuclear fuel pellets, the combination of high burnup and low temperature drives a microstructural change, leading to the formation of the high burnup structure (HBS). In this work, we propose a semi-empirical model to describe the formation of the HBS, which embraces the polygonisation/recrystallization process and the depletion of intra-granular fission gas, describing them as inherently related. For this purpose, we performed grain-size measurements on samples at radial positions in which the restructuring was incomplete. Based on these new experimental data, we infer an exponential reduction of the average grain size with local effective burnup, paired with a simultaneous depletion of intra-granular fission gas driven by diffusion. The comparison with currently used models indicates the applicability of the herein developed model within integral fuel performance codes

Micro-acoustic techniques for the elastic properties investigation of severe accident nuclear fuel

International audienc

High frequency acoustic microscopy for the determination of porosity and Young’s modulus in high burn-up uranium dioxide nuclear fuel.

International audienc

Elastic properties of severely degraded fuels

International audienc