Electrical conductivity change in single crystal Al 2O 3 and MgO under neutron and gamma-ray irradiation

Abstract

In situ electrical conductivity measurements under reactor and gamma-ray irradiation were carried out for Al 2O 3 and MgO specimens using JRR-3 and a 60 Co gamma-ray irradiation facility at JAERI. The specimens were irradiated in the temperature range 573 to 723 K for two cycles (about 0.2 dpa) with an applied dc electric field of 100 V/mm. The conductivity level evaluated after the shutdown of the reactor was substantially smaller than those during the reactor operation. Thus, it was considered that radiation induced electrical degradation (RIED) did not occur or was a negligibly small level, up to 0.2 dpa for Al 2O 3 and MgO specimens. The conductivity of the Al 2O 3 specimen evaluated at various reactor powers in JRR-3 was consistent with that measured under the 60 Co gamma-ray irradiation and was in fairly good agreement with the other radiation induced conductivity (RIC) data of high-purity Al 2O 3.