The high-dose and high-temperature monitors of reactor irradiation based on insulators

Radiation-induced changes of the structure and properties have been investigated for oxide and nitride materials, and the use of high-temperature insulators as temperature/dose monitors for in-reactor irradiation of materials test assemblies has been validated.It has been experimentally shown that the use of Al2O3 single crystals and BN ceramics provides means of monitoring the temperature of irradiation from 370 to 1900 K. The temperature is derived from measurements of the optical absorption or X-ray diffraction line shifts after post-radiation annealing of the monitors. We discuss the applicability of (a) the optical absorption and F-center luminescence spectroscopies of irradiated Al2O3 single crystals for gamma dose evaluation and (b) the isotopic analysis of irradiated BN ceramics for neutron dose evaluation.