In-situ X-Ray diffraction for ionic-covalent material study under swift heavy ion irradiation
Résumé
Due to increasing technologic interests for ceramics in electronuclear industry, studies of the evolution of material properties under swift heavy ion irradiation are highly topical. The effects of electronic excitation on structural properties for insulating ceramics has been highlighted, numerous questions are still remaining about driving forces which induce structural parameter evolutions. In this context, at IRRSUD beam-line (GANIL-Caen), which delivers typical 2 ions of fission products, an X-Ray diffractometer has been recently set up on line to get easy 7 access to phase transition kinetics under irradiation. It prevents problems of sampling variations and it offers possible combination of numerous irradiation parameters which is fundamental for phenomena understanding. By tilting the goniometer and using special vacuum chamber for ion beam propagation, in-situ grazing XRD measurements are possible during irradiation, the grazing configuration allowing the analysis of the only irradiated region. The communication will present the first results obtained on this device. As school cases for structural study, some insulating ionic-covalent materials have been picked up. Combination with microstructural analysis by transmission electron microscopy and point defect study by optical spectroscopy will be presented. Evidences with ion doses of latent tracks, amorphization or phase transitions will be highlighted.