THE EFFECT OF THE EXPOSURE TO DIFFERENT IRRADIATION SOURCES ON THE THERMAL-CONDUCTIVITY OF AL2O3

The high temperature thermal conductivity of A12O3 exposed to the radiation of four different sources (neutron and α-particles) is measured by a laser flash technique. In addition, annealing experiments are performed in the temperature range from 300 to 2000 K in vacuum (10-5 mbar). The reduction of thermal conductivity due to radiation induced defects is not a function of the damage dose alone but depends strongly on irradiation temperature. The number of stable point defects in the irradiated samples is estimated using a microscopic model which describes the reduction of thermal conductivity in terms of point defects and extended (3D) defects introduced by the irradiation process. © 1990.