Quantitative APT analysis of solid transmutants in ferritic-martensitic steels after irradiation in SINQ targets: Experimental validation of neutronic calculations

Abstract

The properties of materials applied in fission and fusion reactors and targets of spallation neutron sources can be greatly degraded by radiation-induced transmutants. A precise prediction of the production of transmutants is highly important for the safety assessment of these facilities. The prediction is normally made using neutronic calculations. Experimental validation of the calculation results is essentially necessary, but usually very challenging. In the present work, a quantitative analysis of transmutants in ferritic-martensitic (FM) steels F82H, Eurofer 97, and ODS Eurofer after irradiation at 9.6 and 19.6–21 dpa in the SINQ targets was performed using Atom Probe Tomography (APT). The results indicate that solid transmutants Ti, Sc, Ca, K, Cl, and S can be precisely measured and a gas element Ar could also be detected. The difference between the measured concentrations and that calculated with the MCNPX code is less than 30% for most of detectable nuclides of the transmutants. This work demonstrates that the neutronic calculations applied to STIP irradiation experiments are reliable. © 2021 Elsevier B.V.