Application of synchrotron radiation to analyze the precipitation in ODS materials before irradiation in Fe–9%Cr single grain of powder and consolidated Fe–18%Cr

Oxide Dispersion Strengthened (ODS) materials are candidates for structural components of GEN IV and fusion reactors. These materials are reinforced by nano-oxides (size of the smallest <3 nm) and the excellent mechanical properties obtained with such materials have to be kept in service.The aim of this paper is to present the capabilities of the synchrotron radiation to finely characterize the dispersion of second phases in ODS steels (Fe–9%Cr single grain of powder and consolidated Fe–18%Cr) and to study the precipitation mechanisms. This paper illustrates the results from first analyses performed on various unirradiated ODS steels elaborated at CEA using X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) at the Multi-Analysis on Radioactive Sample (MARS) beamline of the SOLEIL synchrotron facility.The complementarities of both techniques, XRD and XAS, especially well appropriated to structural and local environment analyses for nano particles are presented. Results obtained with synchrotron radiation are also enriched by comparison with Transmission Electron Microscopy (TEM) observations performed on similar samples.