HYDROGEN PENETRATION THROUGH STRUCTURAL-MATERIALS UNDER ION-BOMBARDMENT

Hydrogen penetration through the materials is very important for the p rediction of the tritium accumulation in materials and tritium penetra tion into the environment. These processes are connected with the poss ible loss of expensive thermonuclear fuel from a thermonuclear reactor and with TR safety. The experimental results showed the hydrogen pene tration through investigated materials depended greatly on the conditi ons of the penetration (penetration of the hydrogen from gaseous phase , from the glow discharge plasma, under hydrogen ion bombardment). Pre liminary irradiation by the helium ions up to the fluence 1.0 x 10(20) -5.0 x 10(22) ions/m(2) (35 keV He+) caused a strong decrease in hydro gen penetration through investigated materials during hydrogen ion bom bardment as well as simultaneous irradiation by hydrogen and helium io ns. The results obtained showed that the preliminary implantation of t he O,N,C impurities into the surface layer of the sample had a strong effect on the hydrogen penetration through examined materials.