Neutronics and Activation Analysis of Aluminized RAFM Steel

Reduced-activation ferritic-martensitic steel (RAFM), such as F82H, is used in the Fusion Energy System Studies–Fusion Nuclear Science Facility as a structural material for the blanket. Previous research has identified significant issues with corrosion and tritium permeation due to the liquid metal Pb-17Li. To address these issues, aluminum or aluminum-based coatings have been proposed. This study performs a neutronics analysis of a blanket incorporating an aluminum-based coating layer, evaluating parameters such as tritium breeding ratio, nuclear heating (neutron and photon), and radiation damage. Low volume percentages (0.1% to 1.25%) of aluminum or FeAl are mixed with RAFM steel, and the analysis is conducted using OpenMC with the FENDL-3.2b library. The results show that the impact of the aluminum-based coating on these parameters is minimal, with changes within 0.6% compared to the non-coated case. Additionally, given that aluminum contains a long-lived isotope, Aluminum-26, an activation analysis was performed to evaluate its specific activity.