• Under combined irradiations, irradiation resistance follows: W-K > W-Y 2 O 3 > PW. • The evolution of fuzz thickness under irradiations follows: W + +He > He > W + +He + EB. • The crack width and surface roughness under irradiations: W + +He + EB > EB > W + +EB. One of the key challenges for tungsten as plasma-facing material in future fusion devices is its exposure to the combined effects of high-energy neutron irradiation, high-flux plasma exposure, and intense thermal loads. To address the challenges, a variety of advanced tungsten-based materials have been developed and part of their performance has been investigated. In this paper, we focused on the tungsten strengthened by Y 2 O 3 (W-Y 2 O 3 ), the tungsten doped with potassium (W-K) and pure tungsten (PW) prepared using the same processing techniques. These tungsten-based material specimens were subjected to various combined irradiation conditions, including 7 MeV W ions pre-irradiation (W + ), helium plasma exposure (He), and pulsed electron beam irradiation (EB). The evolution of fuzz nanostructures and surface cracking behavior was systematically characterized. The results indicate that the influence of irradiation conditions on fuzz thickness follows the trend: W + +He > He > W + +He + EB. The W + ion pre-irradiation amplifies the defect-sink effects providing by W materials doped K pipes/bubbles and the dispersed Y 2 O 3 strengthening particles, demonstrating the material-dependent fuzz evolution trend: PW > W-Y 2 O 3 > W-K. Regarding thermal shock resistance, the influence of irradiation conditions on main crack width and surface roughness follows the order: He + EB > W + +He + EB > EB > W + +EB. However, the combined irradiation conditions have a weak effect on the overall crack area ratio. Among the three materials, W-K exhibits better irradiation resistance than W-Y 2 O 3 and PW. The possible reasons for the observed surface and microstructure evolution are also discussed.
Wang et al. (Fri,) studied this question.