M. Matijasevic (Sp), A. Almazouzi, SCK-CEN, Mol (Belgium)
High chromium ( 9-12 wt %) ferritic/martensitic steels are candidate as potential first-wall and breeding blanket structural materials for future fusion reactors and Accelrator Driven Systems ( ADS). Their use for these applications requiers a careful assessment of their mechanical stability under high energy neutron irradiation and in aggressive environments. In particular , the Cr concentration has been shown to be a key parameter to be optimised in order to guarantee the best corrosion and swelling resistance, together with the least embrittlement. The chemical compositon of high-chromium steels can minimise the level of activation after neutron irradiation ( so called reduced-activation ferritic-martensitic RAFM steels), without significant loosing of mechanical properties , compared with conventional steels. A better understanding of this material and their properties requires an in-depth characterisation of the microstructure in parallel to a rational comparison between microscopic features and macroscopic properties.
this presentation reports on our first results concerning the investigation of Fe-Cr model alloys with well controlled chemical composition and microstructure before and after irradiation at 300°C in BR2 reactors.