Tritium permeation through the first wall of the EU-HCPB blanket

The Helium Cooled Pebble Bed (HCPB) blanket is one of the two concepts to b e further developed for a European DEMO power reactor. Tritium leakage due to the permeation through the main structural materials constitutes one of the main problems of the fusion technology. In the present work, the tritiu m permeation through and inventory in the first wall between the plasma and the first wall coolant has been evaluated. The influence of temperature gr adient, surface conditions, isotopic effect, and trapping in ion- and neutr on-induced defects on the hydrogen isotope permeation and inventory has bee n considered. (C) 2000 Elsevier Science B.V. All rights reserved.