The influence of implanted helium on nickel radiation resistance under conditions simulating plasma flux disruption in nuclear fusion reactor

The paper presents the results on Nuclear Fusion Reactor (NFR) first wall materials radiation erosion caused by a series of impulses to simulate plasma disruption and by 40 keV helium ion fluxes with doses 2x1021m-2 and 1x1022m-2. The series in question consisted of 2-10 impulses of high-temperature D-plasma fluxes (IHTPF) with incident power density up to 2x1010W/m2. Prior exposure to IHTPF has been found to come a substantial increase of the material resistance to erosion under the action of subsequent ion irradiation. Exposure to IHTPF at the late stages of ion bombardment results in a sharp change of material (material surface) structure with new blisters appearing and breaking with open porosity and cracking. At the high doses of ion bombardment (Φ>Φth) an almost complete helium release is observed while at lower doses (Φ<Φth) only about 50%. 7 refs.; 3 figs.; 2 tabs