Macroscopic rate equation modeling of trapping/detrapping of hydrogen isotopes in tungsten materials

JOURNAL OF NUCLEAR MATERIALS

卷:467

Article

Hodille, E. A.¹  Bonnin, X.²  Bisson, R.³  Angot, T.³  Becquart, C. S.⁴  Layet, J. M.³  Grisolia, C.¹ 

[1] CEA, IRFM, F-13108 St Paul Les Durance, France

[2] Univ Paris 13, Sorbonne Paris Cite, LSPM CNRS, F-93430 Villetaneuse, France

[3] Aix Marseille Univ, CNRS, PIIM, UMR 7345, F-13397 Marseille, France

[4] Univ Lille 1, UMET, F-59655 Villeneuve Dascq, France

关键词: fuel retention;    deuterium;    tungsten;    modeling;   

DOI  :  10.1016/j.jnucmat.2015.06.041

来源: Elsevier

【 摘 要 】

Relevant parameters for trapping of Hydrogen Isotopes (HIs) in polycrystalline tungsten are determined with the MHIMS code (Migration of Hydrogen Isotopes in MaterialS) which is used to reproduce Thermal Desorption Spectrometry experiments. Three types of traps are found: two intrinsic traps (detrapping energy of 0.87 eV and 1.00 eV) and one extrinsic trap created by ion irradiation (detrapping energy of 1.50 eV). Then MHIMS is used to simulate HIs retention at different fluences and different implantation temperatures. Simulation results agree well with experimental data. It is shown that at 300 K the retention is limited by diffusion in the bulk. For implantation temperatures above 500 K, the retention is limited by trap creation processes. Above 600 K, the retention drops by two orders of magnitude as compared to the retention at 300 K. With the determined detrapping energies, HIs outgassing at room temperature is predicted. After ions implantation at 300 K, 45% of the initial retention is lost to vacuum in 300 000 s while during this time the remaining trapped HIs diffuse twice as deep into the bulk. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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