Composite effect of helium ion irradiation and transient thermal shock on recrystallized pure W and W-Y2O3 alloys

Abstract

Tungsten (W) is the material of choice for the thermal nuclear fusion reactors of the future. In this research, pure W (PW) and W-Y2O3 alloys made by the SWIP (Southwestern Institute of Physics) wet chemical process are chosen. Simulation of long-term extreme operating conditions of fusion reactor materials by annealing and recrystallization of forged tungsten materials. The thermal shock resistance of recrystallized PW and W-Y2O3 alloys to radiation by helium (He) ions at a flux of 1.4 × 1022 ions/(m2s) was investigated. The surface microscopic pictures of recrystallized W and W-Y2O3 alloys were analyzed using scanning electron microscopy (SEM) and a laser surface profiler under the conditions of helium ion irradiation and electron beam transient thermal shock. After helium ion irradiation, the surface of PW and W-Y2O3 alloys exhibits a fuzzy structure. Under the same 0.33 GW/m2 thermal shock condition, the average width of the main cracks of PW and W-Y2O3 alloys significantly increases after helium ion irradiation, indicating that helium ion irradiation can reduce the thermal shock resistance of the surface of recrystallized W materials.