Current Research and Development Activities on Tritium Permeation Barriers for Fusion Reactor in China

Tritium permeation barrier(TPB) on structural materials is one of key scientific and technological issues for preventing the tritium loss from fusion plants. The paper reviews present status of studies and developments of materials, engineering processes and mechanisms resisting H-permeation of tritium permeation barriers in China, subsidized by national magnetic confinement fusion science program of China, comparing to the TPB developments in Europe, India and Japan, etc. Oxides as TPB material are of special interest and their corresponding processes are being optimized and updated. Processing scale and H-resisting efficiency of Al₂O₃/FeAl TPB by electrochemical Al coating(ECA), pack coating(PC) and hot-dip aluminizing(HDA) in China are in comfortable lead. Mechanisms of TPB resisting H-permeation proposed from the basic point of view are very important to comprehend the results from the common method based on Fick’s law. TPB with long life and high H-resistance performance and its process are needed to develop in the future.