Helium irradiation behavior of tungsten-niobium alloys under different ion energies

Tungsten is a primary material in plasma-facing components (PFCs), but several disadvantages limit its application in fusion reactors. This work examined tungsten–niobium (W–Nb) alloys as potential PFC materials and investigated their response to low-energy helium ion irradiation. W–Nb powders were milled for 25 and 36 h, and the W–Nb samples were exposed to 50 and 80 eV helium ion irradiation with a flux of 1.5 × 10²² ions/m² s at 1230 °C. The sample with a dense structure and obtained after a 25-h milling exhibited enhanced anti-irradiation performance. Sufficient energy can be provided to promote helium ion migration in the matrix, resulting in the formation of nanotendrils. Furthermore, in W–Nb alloys, the Nb-rich regions are more attractive to helium ions and thus provide protection to the tungsten matrix.