Study of Combined Effect of Helium Ion Implantation and Pulsed Laser Radiation on the Structure and Microhardness of the Surface of V–10Ti–6Cr–0.05Zr–0.1Si Alloy

The effect of preliminary He+ ion implantation on the morphology and microhardness of the surface of vanadium alloy V–10Ti–6Cr–0.05Zr–0.1Si upon subsequent exposure to high-power pulsed laser radiation has been studied. Low-activation vanadium-based structural materials are the most corrosion-resistant with respect to Li. They are promising for reactors with a liquid blanket version, where lithium is a coolant and tritium is a reproducible material. Helium ion implantation into alloy has been carried out in an ion-beam accelerator. General patterns of surface destruction have been established for both the original samples and those preirradiated with helium: formation of a hole surrounded by a breastwork and a heat-affected zone located behind the breastwork. The surface erosion is higher in samples implanted with helium: more intense material boiling inside the hole, the formation of a breastwork in the form of an annular rim, and the formation of areas of three types in the heat-affected zone are observed. It is found that the microhardness of the alloy surface after He+ ion implantation and in the holes formed under subsequent exposure to laser radiation practically does not change (within the measurement error) and the microhardness in the holes of the original alloy first decreases when exposed to laser radiation, and then with an increase in the number of pulses, there is a tendency to its increase. The mechanisms of the observed phenomena are discussed.