Heavy-Ion Irradiation for Rapid Evaluation of In-Reactor Nuclear Fuel Behavior

Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), Technical University of Munich, 85748 Garching, Germany

Published online: 13 May 2026

Abstract

Heavy-ion irradiation provides a powerful surrogate technique to study and quantify in-reactor fuel behavior under well-controlled laboratory conditions. This work presents results from uranium-molybdenum (UMo) fuel studies conducted at the Maier-Leibnitz Laboratory (MLL) of the Technical University of Munich, where energetic heavy ions are used to simulate fission fragment effects. By comparing ion-irradiation data with in-reactor results, a strong quantitative correlation is demonstrated for the growth kinetics of the interdiffusion layer (IDL) between UMo and Al, its temperature-dependent microstructural evolution, and the performance of diffusion barrier coatings. Furthermore, high-dose ion irradiation reproduces irradiation-induced restructuring in UMo, confirming the capability of the method to simulate high-burnup phenomena. These results highlight how accelerator-based nuclear physics techniques can be applied to materials research, directly reflecting the HIAS 2025 theme of Nuclear Physics and its Applications. Ongoing and future collaborations, including test irradiations at the Heavy Ion Accelerator Facility (HIAF) at the Australian National University, aim to expand this approach to new accelerator environments and strengthen its role in the qualification of next-generation research reactor fuels.