Microstructural investigation, using small-angle neutron scattering, of neutron irradiated Eurofer97 steel

Abstract This contribution presents the results of small-angle neutron scattering (SANS) measurements carried out to investigate the microstructure of Eurofer97 neutron irradiated with 2.7 dpa, at 60 °C and 300 °C. For comparison, samples of a laboratory heat of this same steel, irradiated under the same conditions, have also been investigated. The SANS measurements have been carried out at the High Flux Reactor of the ILL-Grenoble. SANS data analysis, based on the comparison of nuclear and magnetic scattering, shows that the microstructural defects produced under irradiation are mostly non-magnetic ones (He bubbles, microvoids). Their distribution strongly varies with the irradiation conditions, namely with increasing irradiation temperature. A consistent increase is observed both in the average size (up to approximately 100 A) as well as in the volume fraction.