Decreased surface blistering and deuterium retention in potassium-doped tungsten exposed to deuterium plasma following ion irradiation
Xiaolei Ma, Xiaoxin Zhang, Ting Wang, Yuan Gao, Yue Yuan, Long Cheng, Jipeng Zhu, Wei Lv, Shaoting Lang, Changchun Ge, Qingzhi Yan
Abstract
Abstract A large-size potassium-doped tungsten (KW) plate with a thickness of 15 mm was fabricated via powder metallurgy technology and hot rolling. In order to appraise the irradiation resistance of KW, the surface deuterium (D) blistering and D retention were studied on Fe 11+ pre-damaged (0, 0.05 and 0.5 dpa) KW and pure tungsten (PW), which were exposed to ∼60 eV and ∼5 × 10 21 m −2 s −1 D plasmas at 500 K at a fluence of ∼5.76 × 10 25 m −2 . The results indicate that the KW alloy can better inhibit the generation of vacancy defects after Fe 11+ ion damage compared with PW because K bubbles can restrain the migration of W self-interstitial atoms and the accumulation of vacancies caused during Fe 11+ ion irradiation. The Fe 11+ ion pre-damage can relieve the surface blistering and D retention of PW and KW at the same time, and the KW has a better effect of inhibiting D retention, while it does not show a significant advantage in inhibiting surface blistering compared with PW. In addition, the causes of the discrepancy in total D retention and the surface morphology evolution of PW and KW are discussed in detail.