Swelling, mechanical properties and microstructure of beryllium irradiated at 200 °C up to extremely high neutron doses

The paper reports on an investigation of four beryllium grades (TE-56, TE-30, TIP, DIP) produced in Russia using the technology of hot extrusion (HE) and hot isostatic pressing (HIP). Specimens were irradiated in the SM reactor at a temperature of 200 °C to neutron doses in the range of (0.7–13.1) × 1022 cm−2 (E > 0.1 MeV) and then subjected to post-irradiation examination. Beryllium swelling, microhardness and mechanical tensile and compression tests results as a function of neutron dose are presented. In addition, the paper contains the results of irradiated beryllium microstructure examination. Swelling increases with dose and does not exceed 4%. Microhardness also increases steadily with neutron dose. The irradiation induced embrittlement of all the tested specimens with increasing dose leads to significant decrease of brittle strength. The void size and density tend to increase in the microstructure of irradiated beryllium.