The transition to carbon neutrality requires a rapid increase in low-carbon energy sources, including nuclear power, which necessitates a deep understanding of irradiated materials. Mixed oxide (MOX) fuel is particularly important as it optimizes the use of nuclear resources and reduces radioactive waste. The mechanical behavior of MOX under irradiation is crucial for ensuring the integrity of the fuel under various operating conditions.

The objective of this thesis is to perform atomistic simulations to understand dislocation mobility, essential for supporting multiscale modeling of the mechanical behavior of MOX. Molecular dynamics calculations will analyze dislocation mobility under different conditions of temperature, stress, plutonium content, and stoichiometric deviations, with the aim of establishing velocity laws. The results of these simulations will enhance micromechanical modeling within the CEA’s PLEIADES simulation platform, which is dedicated to simulating the complete lifecycle of nuclear fuel, from its fabrication to its storage.

The doctoral student will be based at the Fuel Behavior Modeling Laboratory in Cadarache, a dynamic environment with 11 permanent researchers and an equal number of doctoral students. Located in Provence, this center offers a pleasant working environment between the Verdon and Lubéron natural parks. The thesis will be carried out in collaboration with IM2NP, a leading laboratory in materials physics research.

The candidate should have a strong background in materials physics, ideally with experience in small-scale mechanics. These skills can be further developed during an M2 internship at the laboratory. The doctoral student will have the opportunity to present their work through scientific publications and at international conferences, opening up career opportunities in both research and industry.