Plasma induced material defects and threshold values for thermal loads in high temperature resistant alloys and in refractory metals for first wall application in fusion reactors

Materials for the application in the first wall of fusion reactors of the Tokamak type are subjected to pulsed heat fluxes which range from some 0.5 MW m$^{-2}$ to 10 MW m$^{-2}$ during normal plasma operation, and which can exceed 1000 MW m$^{-2}$ during total plasma disruptions. The structural defects and material fatigue caused by this types of plasma wall interaction are investigated and the results are plotted in threshold loading curves. Additionally, the results are, as far as possible, compared with quantitative, theoretical calculations. These procedures allow a semiquantitative evaluation of the applicability of the mentioned metals in the first wall of fusion reactors