Graphite as a first wall material for thermonuclear fusion devices

Various candidate materials for the first wall of the magnetically confined thermonuclear fusion devices have been widely investigated. Among these candidates, graphite is one of the most promising materials because of its low-z, refractory nature, high heat conductivity, and ease in fabrication, etc. In spite of graphite's superb properties, many problems which would obstruct its actual use are still left to be solved. In this paper, the present status and the current objectives of a graphite first wall which concern fuel recycling and inventory are reviewed from the viewpoint of [1] surface characterization and radiation damages caused by ion bombardment, [2] trapping and reemission of hydrogen isotope atoms, [3] trapped states, thermal desorption behaviors and recombination factors of hydrogen isotopes, and [4] surface modification by other elements. (author)