Influence of point defect concentration on the generalized stacking‐fault energy in uranium dioxide

Abstract Stacking‐fault energy is a fundamental material property that significantly affects the shearability of crystalline materials by influencing the behavior of dislocations. Here, the impact of point defects on the stacking‐fault energy in nuclear fuel is investigated using a large‐set of molecular statics simulations combined to statistical analysis. A focus is made on the excess stacking‐fault energy induced by uranium Frenkel pairs usually produced during high‐temperature irradiation, in the main slip systems of the fluorite structure. The results show quantitative changes of the stacking‐fault energy that can vary up to several hundreds with point defect content, what might significantly influence dislocation core, mobility and more broadly, the mechanical behavior of the material. These results highlight the crossed link of point defects upon nuclear fuel mechanics and pave the way for further investigations into dislocation‐point defect interactions, particularly in the context of high‐temperature nuclear fuel applications.