Simulation of radiation effects on reflectors using heavy ion beams

The results on modelling the behaviour of metal mirrors under neutron irradiation in a fusion reactor are presented. Mirror-like specimens were irradiated with beams of ions: Cr+ (stainless steel), Cu+ (copper) and Ne+ and/or He+ (beryllium). The energy of ions was in the range of a few keV (He+) to 3 MeV (Cr+ and Cu+). The reflectivity as a function of irradiation dose was measured in the interval of spectrum 0.2-1.0 μm. There was no strong degradation of the mirror reflectivity up to doses similar 10 dpa in a near surface layer. In contrast, all used methods showed definite change of surface characteristics. ((orig.))