NEUTRON ACTIVATION AND GAS PRODUCTION IN TITANIUM AND CHROMIUM BERYLLIDES IN FISSION AND FUSION NEUTRON FIELDS

Beryllium-based intermetallic compounds are considered promising functional and structural materials for advanced nuclear systems due to their favorable neutronic, thermal and activation characteristics. In this work, neutron-induced activation in titanium and chromium beryllides (Be12Ti and Be12Cr) containing technological impurities was investigated under fission and fusion neutron environments. Experimental gamma-spectrometric measurements and Monte Carlo calculations were performed for specimens irradiated in the WWR-K research reactor. Agreement between calculated and measured specific activities for the dominant activation products Sc-46, Mn-54, Fe-59 and Cr-51 confirms the applicability of the neutronics approach. Neutron-induced gas production (He-4, He-3, T and Li-6) was additionally evaluated for an ITER-relevant D-T spectrum under fixed-fluence conditions. The results demonstrate pronounced spectrum-dependent differences in activation and transmutation behaviour and provide a basis for extrapolating fission-irradiation data to fusion-relevant conditions.

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