Electrical conductivity of alumina after heavy irradiation in a high-flux fission reactor

Abstract

The electrical conductivities of seven different alumina specimens were measured after they were irradiated in the High-Flux Isotope Reactor (HFIR), Oak Ridge National Laboratory. Results indicated a moderate increase in the electrical conductivity due to the irradiation in HFIR up to 2.8 displacements per atom at 450–500°C. A large offset current was observed in the irradiated specimens after they were subjected to an applied voltage, which indicated the existence of a large number of trapped electrical charges. An abrupt release of the trapped electrical charges may be a trigger to cause the previously reported electrical breakdown under irradiation (called radiation-induced electrical degradation).