Ceramic breeder research and development: progress and focus

The world-wide efforts on ceramic breeder materials in the last two years c oncerned Li2O, Li4SiO4, Li2TiO3 and Li2ZrO3, With a clear emphasis on the d evelopment of Li2TiO3. pebble-manufacturing processes have been developed u p to a 10 kg scale. Characterisation of materials has advanced. A jump-wise progress is observed in the characterisation of pebble-beds, in particular of their thermo-mechanical behaviour. Thermal property data are still limi ted. A number of breeder materials have been or are being irradiated in mat erial test reactors like HFR and JMTR. The EXOTIC-S series of in-pile exper iments is a major source of tritium release data. This paper discusses the technical advancements and proposes a focus for further research and develo pment (R&D) : pebble-bed mechanical and thermal behaviour and its interacti ons with the blanket structure as a function of temperature, burn-up, irrad iation dose and time; tritium release and retention properties; determinati on of the key factors limiting blanket life. (C) 2000 Elsevier Science B.V. All rights reserved.