Assessment of tungsten for use in the ITER plasma facing components

Tungsten is one of the candidate armor materials for the plasma facing comp onents of the International Thermonuclear Experimental Reactor (ITER). For the present reference design, tungsten has been selected as armor for the d ivertor upper vertical target, dome, cassette liner, and for lower baffle b ecause of its unique resistance to ion and charge-exchange particle erosion in comparison with other materials. The issues related to the use of tungs ten in ITER are described in this paper. The different tungsten grades (pur e, dispersion strengthened and cast alloys) which are being considered as c andidate materials are evaluated. A comparative analysis has been made of t he mechanical properties of the various tungsten grades in different thermo mechanical conditions, including the impact of irradiation effects. The dif ferent tungsten armor design solutions are also described. (C) 1998 Elsevie r Science B.V. All rights reserved.