[2B01-05] Hydrogen Isotope Behavior

[2B03] The effect of deuterium plasma implantation on deuterium retention behavior for heavy ion implanted W.

*Keisuke Azuma¹, Yuki Uemura¹, Shodai Sakurada¹, Hiroe Fujita¹, Qilai Zhou², Naoaki Yoshida³, Takeshi Toyama⁴, Sosuke Kondo⁵, Takumi Chikada¹, Yasuhisa Oya¹ (1. Graduate School of Science & Technology, Shizuoka Univ., 2. Faculty of science, Shizuoka Univ., 3. Insitute for Applied Mechanics, Kyushu Univ., 4. Institute for Materials Research, Tohoku Univ., 5. Institute of Advanced Energy, Kyoto Univ.)

Keywords:Tungsten, Plasma implantation, Heavy ion implantation, Deuterium retention behavior

Tungsten (W) is considered to be a candidate for plasma facing materials (PFMs) in fusion reactor. It will be exposed to energetic neutron escaped from plasma during the plasma operation. In that time, implantation defects which trap hydrogen isotope, will be introduced. In our previous study, D retention behavior in damaged W by iron ion implantation to simulate the implantation defect was estimated by D₂⁺ implantation. In the actual fusion reactor, W will be exposed to low energy and high flux hydrogen plasma. Therefore, hydrogen isotope retention behavior in plasma irradiated W is expected to be quite different from that of ion implanted W. In this study, D retention behavior for Fe²⁺ damaged W with D plasma was compared to that with D₂⁺ ion implantation. From this experiment, it was suggested that D was trapped by the defect in order from surface to bulk in comparison to D₂⁺ ion implanted W. The HIDT simulation is applied to estimate of trapping energy of hydrogen isotopes in damaged W and D plasma irradiation effect will be discussed.