[3N08-13] Plasma Facing Materials

[3N09] Hydrogen isotope removal from neutron-irradiated tungsten by baking out

*Yuji Hatano¹, Vladimir Kh. Alimov^2,4, Takeshi Toyama², Tatsuya Kuwabara³, Alexander V. Spitsyn⁴, Youji Someya⁵ (1. Univ. of Toyama, 2. Tohoku Univ., 3. Aichi Inst. Technol., 4. NRC Kurchatov Inst., 5. QST)

Keywords:Tugsten, Hydrogen isotope, Neutron irradiation, Tritium, Decontamination

One of the possible tiritium removal methods from plasma-facing component (PFCs) is to heat PFCs to ~300 ℃ in a vacuum vessel after DT operation using decay heat. In this study, W samples were irradiated with neutrons in a fission reactor BR2 to 0.016 dpa, and release of deuterium (D) in a vacuum at 300 ℃ from the irradiated and non-irradiated W samples was examined after exposure to high flux D plasma at 300, 400 and 500 ℃. The majority of D retained in the non-irradiated samples was released by heating for 30 h. Far slower but clear release of D was observed for the neutron-irradiated samples. The possible D removal by heating for longer time (~1 month) will be simulated using diffusion analysis code with parameters obtained by this experiment and measurements of thermal desroption spectra.