Selective sputtering of eurofer steel by deuterium plasma

The selective sputtering of reduced-activation ferritic-martensitic steel Eurofer upon deuterium plasma irradiation with ion energy of 100 eV is investigated. The experiments are carried out at 550 K and the radiation-dose range of (3–70) × 1024 ion/m2, and in the temperature range 350–730 K at fixed a radiation dose of 3 × 1025 ion/m2. The sputtering-coefficient dependences and information about the complex relief formed on the surface of Eurofer steel under ion irradiation are obtained. The elemental composition of the surface layer is studied by energy-dispersive X-ray spectroscopy and Rutherford backscattering. Enrichment of the surface layer with tungsten is found, which increases with the fluence of plasma irradiation. At the maximum radiation dose, the concentration of tungsten on the surface, averaged over an area of the analyzing beam of 1.7 mm2, was increased by about 13 times and reached a value of about 6 at % (about 14 wt %).