Impact of hafnium content on nuclear performance of breeder and multiplier materials containing zirconium in fusion assemblies

The reduction of hafnium content in blanket materials containing zirconium is costly. Therefore, a sensitivity analysis was performed to estimate the impact of hafnium content on nuclear properties of lithium metazirconate Li₂ZrO₃ and of Zr₅Pb₃, promising breeder-multiplier system candidate for fusion reactors. This paper summarises the results of extensive shielding neutronic analysis and transmutation-activation calculations aiming to evaluate the tritium breeding ratio, the inventories of various radio nuclides, and the surface γ-dose rate, both for breeder and multiplier materials containing hafnium impurities. 1-D neutron transport fixed source analysis has been performed with the XSDRNPM code, using the 171-group VITAMIN-C cross section library, based on ENDF/B-V and JEF2.2 basic data. The activation calculations were performed with the ANITA code, using updated cross section and decay data libraries based on EAF-3 evaluation files. A comparison between Zr₅Pb₃ and beryllium multipliers in different design configurations including homogenised solid breeder mixtures of Li₂ZrO₃ and structural materials has been performed