The effect of neutron irradiation on beryllium performance

This paper considers the effect of neutron irradiation on the performance of six beryllium grades (DshG-200, TR-30, TshG-56, TRR, TE-30, TIP-30) fabricated by VNIINM, Russia, and one fabricated by Brush Wellman, USA, S-65. The average grain size of the beryllium grades investigated varied from 8 to 40 μm, beryllium oxide content was 0.7–3.2 wt.%, initial tensile strength 250–680 MPa. All the specimens were irradiated in the active zone of a SM-3 reactor at 650–700°C up to the fast neutron fluence (5.5–6.2)×1021 cm−2 (helium content up to 1150 appm), E>0.1 MeV. Beryllium behaviour under tensile and compressive tests, swelling and microstructure examination before and after irradiation are presented. The effect of neutron-induced embrittlement on thermal shock resistance of beryllium and its role in the selection of the beryllium grade for HHF-components of ITER are discussed.