Erosion and deuterium retention in ion-irradiated tungsten under plasma exposure

Abstract Effect of radiation damage on tungsten response to plasma exposure is examined. Samples of tungsten W 99.95 wt% were irradiated with fast 12 C 3+ ions at 10 MeV to fluence of (1–2) × 10 17  ion/cm 2 to produce damage in the range 1–40 dpa relevant to the level of interest for fusion research. Exposure of the irradiated tungsten to deuterium plasma on linear simulator in erosion condition provided D-ion total fluence (1–3) × 10 21  D + /cm 2 at ion energy 250 eV. Swelling effect has been observed, and important changes in the structure of the irradiated material have been found (SEM). Erosion of the damaged layer was evaluated at Y d-w  ≅ (3–5) ⋅ 10 −3  at/ion. The retained deuterium profiles have been taken by ERDA, maximal deuterium concentration reached 6–8 at.% in the layer ∼30 nm deep corresponding to 2–3 dpa. Comparison of D-retention was made for C- and He-irradiated tungsten for this level of damage.