Multi-temperature neutron irradiation of pure beryllium and beryllides to 2.5–3 dpa in BR2 reactor

This paper reports the current status of neutron irradiation experiments designed to evaluate beryllide (Be$_{12}$V, Be$_{12}$Ti, Be$_{12}$Ti + 1 wt%Be$_{12}$V) and pure beryllium under controlled neutron flux conditions in the BR2 reactor. The target fluence corresponds to 2.5–3 dpa in Fe, achieved over three to four cycles, at four distinct temperatures (400, 600, 750, and 900◦ C) with using dedicated stainless-steel capsules, designed according to the BAMI (Basket for Material Irradiation) concept, which allows fast deployment and high neutron flux without active temperature control or gas flushing. To determine irradiation condition, thermal and neutronic calculations (FEM and MCNP) were conducted. Gadolinium (Gd) is selected as the thermal neutron shield to reduce thermal flux, with its burn-up and reactivity effects assessed for reactor safety. Eight capsules will accommodate different sample geometries (pebbles, disks, and cylinders), filled with helium to ensure inert conditions.