MECHANISM OF TRITIUM RELEASE FROM LITHIUM CERAMICS IRRADIATED WITH NEUTRONS

Out-of-pile tritium release experiments have been performed at CEA/CEN Saclay on several types of lithium ceramics including pure single crystals and sintered pellets and those doped with impurities to alter their tritium release characteristics. The results of these experiments suggest that tritium trapping occurs at low temperature to the extent that only a portion of the total tritium present will be released at low temperature. Doping has the effect of changing the population of the traps. For example, when single-crystal LiAlO 2 is doped with Mg, the amount of tritium trapped at low temperature is decreased, improving the low-temperature release.