Blister formation and deuterium retention on tungsten exposed to low energy and high flux deuterium plasma

Deuterium retention and morphological modifications of the surface in five grades of tungsten after deuterium plasma exposure

“…Specimens of 10x10x2 mm 3 were cut from the Japanese material with their 10x10 mm 2 planes perpendicular to the main deformation direction (WJ). This leads also to elongated grains perpendicular to the specimen surface ("ITER-grade").…”

“…The stepwise energy scan of the incident 3 He beam with the 3 MV tandem accelerator at IPP Garching allows to calculate the depth profile from data. The cross-section of this nuclear reaction peaks at ~620 keV 3 He energy [30].…”

Deuterium retention in tungsten exposed to low-energy, high-flux clean and carbon-seeded deuterium plasmas

“…Data on the D retention in polycrystalline W exposed to low-energy (about 100 eV/D) and high flux (about 1×10 22 m -2 s -1 ) hydrogen isotope plasmas taken from Refs. [21,27,42,45] are shown in Fig. 3 b.…”

Mechanism of vacancy formation induced by hydrogen in tungsten

“…In recent years, hydrogen retention experiments have been carried out to examine the blistering problem. [8][9][10][11][12][13][14][15] The hydrogen retention reaches a maximum around an exposure temperature of 500 K at which a Electronic mail: LGH@buaa.edu.cn 2158-3226/2013/3(12)/122111/12 C Author(s) 2013 3, 122111-1 temperature the most severe blistering phenomena is also observed, and the blistering disappears at 1000 K. 10 The problem of hydrogen bubble formation in metals has been summarized by Condon and Schober, 16 who attributed the formation mechanism in tungsten to the vacancy clustering.…”

“…23 However, the phenomena of hydrogen blistering is indeed observed at the surface of single crystal tungsten under high flux irradiation with quite low energy (not larger than 100 eV). [11][12][13] Such an energy is certainly insufficient to create new vacancies in tungsten. Since the influence of other defects like grain boundaries is excluded, it still remains an open question how the abundant vacancies essentially required by the vacancy trapping mechanism [16][17][18][19] for the hydrogen bubble formation are generated under such a condition and then how hydrogen bubbles are formed.…”