Thermal conductivity of neutron irradiated Be12Ti

Beryllides are expected to be used as the advanced neutron multiplier for the DEMO blanket owing to their peculiar properties like higher melting point, high oxidation resistance, etc. which can improve the blanket design. In this study, thermal conductivity of neutron irradiated Be12Ti was measured. The Be12Ti specimens were fabricated by HIP process using beryllium and titanium powder, and were irradiated in the JMTR up to a fast neutron fluence (E>1 MeV) of 4×1020 n/cm2 at temperatures of 330, 400 and 500 °C. Thermal diffusivity and specific heat of un-irradiated and irradiated specimens were measured up to 1000 °C by laser flash method. Then, the thermal conductivity was evaluated from these data. The effective thermal conductivity in the pebble bed of fusion blanket was also estimated and interesting prospects for blanket design were obtained.