Radiation effects in nuclear materials: Role of nuclear and electronic energy losses and their synergy

Ceramic oxides and carbides are promising matrices for the immobilization and/or transmutation of nuclear wastes, cladding materials for gas-cooled fission reactors and structural components for fusion reactors. For these applications there is a need of fundamental data concerning the behavior of nuclear ceramics upon irradiation. This article is focused on the presentation of a few remarkable examples regarding ion-beam modifications of nuclear ceramics with an emphasis on the mechanisms leading to damage creation and phase transformations. Results obtained by combining advanced techniques (Rutherford backscattering spectrometry and channeling, X-ray diffraction, transmission electron microscopy, Raman spectroscopy) concern irradiations in a broad energy range (from key to GeV) with the aim of exploring both nuclear collision (S-n) and electronic excitation (S-e) regimes. Finally, the daunting challenge of the demonstration of the existence of synergistic effects between S-n and S-e is tackled by discussing the healing due to intense electronic energy deposition (SHIBIEC) and by reporting results recently obtained in dual-beam irradiation (DBI) experiments. (C) 2013 Elsevier B.V. All rights reserved.