Deuterium behaviour in tungsten and graphite at combined stationary and power pulse plasma flow action

Investigations of subsequent irradiation by stationary and power pulsed plasma influence on deuterium retention in tungsten and graphite RGT were carried out. Samples were exposed in stationary plasma of linear simulator LENTA with beam plasma discharge at deuterium ion current density 5·1021 m-2s-l up to fluence 1026 m-2 corresponding to one pulse of ITER at ion energy 200 eV. Temperature of graphite samples were hold at a level corresponding to physical sputtering (1040 K), or at a level corresponding to radiation enhanced sublimation (1400 K). Tungsten samples were irradiated at 800 K. The subsequent irradiation by power pulsed plasma were performed in plasma accelerator MKT at energy flow densities 0.25, 0.50 and 0.90 MJ/m2 per pulse. A significant influence of stationary plasma irradiation temperature on deuterium retention in graphite was established. The concentration of retained deuterium in tungsten after stationary plasma irradiation was observed to be 1.5·1020 m-2, and after subsequent ten pulses in MKT, it decreases on order of magnitude due to deuterium back realise. Deuterium retention in tungsten at stationary plasma exposure after pulsed irradiation is essentially lower than that without pulsed irradiation. Investigation of deuterium retention in the mixed W + C sample was also carried out. (author)