IMITATION OF EFFECTS OF A FUSION-REACTOR ENVIRONMENT ON OPTICAL-PROPERTIES OF METALLIC MIRRORS

Results of imitation experiments on effects of charge exchange atoms b ombardment on optical properties of metallic mirrors (in the spectrum range of 200-800 nm) are presented. The long-term sputtering of mirror samples made of stainless steel, copper and hot pressed beryllium hav e been carried out with plasma ions (H+, D+, He+ or Ar+) of keV energy range. It was shown that in the case of a stainless steel mirror, the sputtering of a layer of similar to 2 mu m thick did not lead to sign ificant change in reflectivity. As to a copper mirror, a noticeable ch ange of reflectivity was observed after sputtering of similar to 0.7 m u m layer using He+ ions. The highest rate of degradation, especially in the UV region, was found in the case of beryllium mirrors.