Effects of double-layer tungsten coatings on hydrogen isotopes plasma-driven and gas-driven permeation through F82H

摘要

The behavior of hydrogen isotopes plasma-driven permeation (PDP) and gas-driven permeation (GDP) through tungsten coated F82H membranes has been studied in the temperature range from 200 ℃ to 550 ℃, using a laboratory-scale steady-state plasma facility. Tungsten coatings have a double-layer structure: the first layer on F82H prepared by sputter-deposition (SP) which is then overlaid with the second layer prepared by vacuum plasma-spraying (VPS). It has been found that VPS/SP double-layer coatings can suppress by orders of magnitude both GDP and PDP of hydrogen isotopes under the plasma-surface interaction conditions relevant to those to be seen nearby the first wall in a DEMO reactor.