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Ferritic-martensitic steels are considered as one of the most promising candidates for structural materials to be used under extreme conditions of temperature and irradiation fluencies. Understanding of the evolution of mechanical properties under these extreme operation conditions is of primary importance. The aim of the work is to advance the knowledge regarding the nanostructure (from the magnetic properties perspective) and its evolution in FeCr alloys under ion irradiation, taking into account that different variables will affect the microstructure and, hence, the behavior of materials under irradiation. The behavior of the Fe-Cr system under irradiation has certain peculiarities, the natures of which are not quite clear yet. The strong hardening and embrittlement inherent to these materials in a radiation field may cause difficulties under extreme conditions of temperature and irradiation fluencies. The main characterisation techniques applied will be: XMCD (X-ray Magnetic Circular Dichroism), XRD (X-ray diffraction) and EXAFS (Extended X-ray Absorption Fine Structure) spectroscopy. Complementary techniques such as TEM (Transmission Electron Microscopy) and PEEM (Photoemission Electron Microscopy) will be used to investigate the ion-irradiated surface layer. The combination of proposed experiments on the ion-irradiated Fe-Cr binary alloy matrix at the nano-scale will allow proper investigations of the influence of magnetism on defect mobility, its effect on precipitation and segregation, and its anisotropic behaviour due to the ferromagnetic/ antiferromagnetic nature of the Fe-Cr alloy matrix which have important implications for the prediction of mechanical properties of Fe-Cr alloys. These investigations will furthermore provide basic information on the material’s plasticity, where assessing clustering and precipitation is necessary due to the hindering nature of precipitates which can pin dislocations and lead to a precipitation hardening effect. Knowledge of the material’s mechanical properties from a fundamental level will lay the foundation of a modeling program which can be predictive, and will greatly impact the scientific community in its study of traditionally experimentally tackled problems.
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