[1G15-17] Hydrogen Isotope Retention for Tungsten

[1G15] Effect of potassium doping on irradiation defect formation and deuterium retention in W

*Kenshiro Miura¹, Yuzuka Hoshino¹, Asahi Sanfukuji¹, Naoko Ashikawa², Qilai Zhou³, Yasuhisa Oya¹ (1. Shizuoka Univ., 2. Kyoto Fusioneering, 3. Wuhan Univ. Tech.)

Keywords:Tungsten, Potassium, Irradiation defects, Hydrogen isotope retention behavior

Tungsten (W) is a candidate material for plasma-facing materials (PFMs) in the D-T fusion reactors. For PFMs will be exposed to fuel particles and neutrons, these irradiation defects lead to the enhancement of hydrogen isotope retention. Previous reports described K-doped W (W-K) was suppressed the embrittlement of W due to high thermal loads and irradiation defects. However, its hydrogen solubility isn’t fully understood. In this study, for W and W-K with irradiation defects introduced by Fe2+ irradiation, these samples were evaluated for the deuterium retention behavior by D+ irradiation, TDS, and the size of defects by PAS. In W-K, the broad peak was observed in the atomic vacancy region. This suggests many small vacancy clusters were generated along grain boundaries.