Challenges of nuclear fusion

After 30 years of research and development in many countries, the magnetic confinement fusion experiments finally seem to be getting close to the original first goal: the point of ''scientific break-even''. Plans are being made for a generation of experiments and tests with actual controlled thermonuclear fusion conditions. Therefore engineers and material scientists are hard at work to develop the required technology. In this paper the principal elements of a generic fusion reactor are described briefly to introduce the reader to the nature of the problems at hand. The main portion of the presentation summarises the recent advances made in this field and discusses the major issues that still need to be addressed in regard to materials and technology for fusion power. Specific examples are the problems of the first wall and other components that come into direct contact with the plasma, where both lifetime and plasma contamination are matters of concern. Equally challenging are the demands on structural materials and on the magnetic-field coils, particularly in connection with the neutron-radiation environment of fusion reactors. Finally, the role of ceramics must be considered, both for insulators and for fuel breeding purposes. It is evident that we still have a formidable task before us, but at this point none of the problems seem to be insoluble. (author)