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The ACE team is composed of two CNRS researchers and two professors/researchers, physical chemists, whose research is related to the problems of nuclear materials and their behavior under extreme conditions and at interfaces. Indeed, whatever the type of nuclear reactor envisaged (fission, fusion) and throughout the nuclear fuel cycle, from upstream to downstream through reactor operation, materials undergo strong chemical and structural modifications due to extreme conditions of temperature and irradiation. It is crucial to understand the fundamental mechanisms that govern the damage of these materials and thus modify their properties. The stakes associated with this research are major, particularly in terms of safety.

All generations of reactors are concerned, such as the first generation of nuclear reactors called UNGG where nuclear graphite was used as a moderator, but also core materials (fuel, structural steel, etc.) of current second and third generation reactors (PWR and EPR) as well as the liquids used or envisaged in the process of reprocessing nuclear waste. This research also concerns carbide-type ceramics envisaged for a fourth generation of reactors whose technology will be a break with the current PWR and EPR. In addition, the impact of radiolysis at interfaces is also a subject of interest.

The approach consists in subjecting these materials to ionizing radiation as well as to thermal treatments (up to 2000°C) and then to characterize the evolution of several physicochemical, mechanical or structural properties of these materials. This approach makes it possible to exacerbate the effects visible in reactors at the laboratory scale in reasonable times. In parallel, an approach by atomistic modeling allows a better understanding of the fundamental mechanisms that govern the effects of irradiation.