Developments of high heat flux components and plasma surface interaction studies in Japan

For the removal of power flow to the divertor, active cooling components which consist of plasma facing materials such as CFC and heat sink material such as OFCu have been very rapidly developed. The present CFC/OFCu brazed material for the ITER divertor can endure the heat load of 25 MW/m(2) and 30 s for more than 1000 heat cycles. For the LHD divertor, several graphite/OFCu brazed materials, which can endure the heat load of 10 MW/m(2) and 30 s for more than 5000 heat cycles was developed. Evaluation studies for low Z plasma facing materials such as Li and B have been progressed. The properties of oxygen gettering and hydrogen uptake were recently examined. Suitable conditioning for plasma facing materials and the use of reliable high heat flux components may largely contribute to the achievement of the burning plasma state over a long time period in future fusion devices. Copyright (C) 1996 Elsevier Science Ltd.