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arXiv · 1909.06815

Effect of gallium doping on bubbling and helium retention in aluminum exposed to low-energy helium plasma

Yao Xiao·Jiliang Wu·Shuoxue Jin·Chunli Jiang·Kai Gu·Lei Li·Yamin Song·Changan Chen·Xingzhong Cao·Xiaoqiu Ye
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Abstract

Surface bubbling and helium retention of pure aluminum and a solid solution of aluminum-gallium(Ga) alloy exposed to low-energy He plasma has been investigated with the fluence of 1.8E24 He/m2 at room temperature . Surface morphology observations show that after irradiation, the average size of He bubbles on Al-1.8 at.% Ga alloy is around 1.8 micro metre, smaller than that on pure Al. Ga doping noticeably increases the area density of the bubble. The thermal desorption spectroscopyshows that the release amount of He in Al-1.8 at.% Ga alloy is 1.77E21 He/m2, nearly three orders of magnitude higher than that in pure Al, whlie the He desorption peak of Al-1.8 at.% Ga alloy is 480 K, much lower than 580 K of pure Al. The results of slow positron annihilation spectroscopy (SPAS) indicate that the vacancy type defects were introduced by He plasma irradiation; and lattice distortion caused by Ga doping plays an important role in determining surface bubbling and He retention characteristics of Al-1.8 at.% Ga.

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Yao Xiao, Jiliang Wu, Shuoxue Jin, Chunli Jiang, Kai Gu, Lei Li, Yamin Song, Changan Chen, Xingzhong Cao, Xiaoqiu Ye. 2019-09-15. Effect of gallium doping on bubbling and helium retention in aluminum exposed to low-energy helium plasma. https://arxiv.org/abs/1909.06815

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