Helium retention of vanadium alloy after energetic helium ion irradiation

• Published in: Fusion engineering and design 2004-10, Vol.70 (4), p.329-334
• Main Authors: Liu, Xiang, Yamada, Tsuyoshi, Yamauchi, Yuji, Hirohata, Yuko, Hino, Tomoaki, Noda, Nobuaki
• Format: Article
• Language: English
• Subjects: Applied sciences; Blister; Controled nuclear fusion plants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Helium retention; Installations for energy generation and conversion: thermal and electrical energy; Thermal desorption spectroscopy; Vanadium alloy
• ISSN: 0920-3796; 1873-7196
• DOI: 10.1016/j.fusengdes.2004.08.001

Helium irradiation experiments of V–4Ti alloy were conducted in an ECR ion irradiation apparatus by using helium ions with energy of 5 keV. The ion fluence was in the range from 1 × 10 17 He/cm 2 to 8 × 10 17 He/cm 2. After the helium ion irradiation, the helium retention was examined by using a technique of thermal desorption spectroscopy (TDS). After the irradiation, the blisters with a size of about 0.1 μm were observed at the surface, and the blister density increased with the ion fluence. Two desorption peaks were observed at approximately 500 and 1200 K in the thermal desorption spectrum. When the ion fluence was low, the retained helium desorbed mainly at the higher temperature regime. As increase of the ion fluence, the desorption at the lower temperature peak increased and the retained amount of helium saturated. The saturated amount was approximately 2.5 × 10 17 He/cm 2. This value was comparable with those of the other plasma facing materials such as graphite.