The paper presents the results of coarse-grained (80 and 100 μm) bulk high-entropy alloys CoCrFeNi and CoCrFeMnNi samples with X-ray diffraction method in non-irradiated and ion irradiated states (He2+, 40 keV, 2×1017 cm-2and Kr14+, 280 keV, 5×1015 cm-2). It is shown, that irradiation causes compressive macrostress development, especially in regions of maximum damage dose and maximum implanted particles concentration. Also helium ion irradiation causes dislocation density increase in irradiated region, and krypton irradiation tends to decrease dislocation density in the area of maximum damage. As observed, more complex CoCrFeMnNi alloys is more resistant to defect formation than more simple CoCrFeNi.

The purpose of this work is to study the effect of irradiation with low-energy helium ions with an energy of 40 keV on the structural-phase state of multicomponent solid solutions based on V-Nb-Ta-Ti. This type of irradiation at fluence of 2×1017 He/cm2 make it possible to simulate the effects occurring in a nuclear reactor. since during its operation, a large number of neutrons are released, causing nuclear reactions in the material with the formation of inert gases. As a result of the work carried out, it was found that all alloys of the system belong to equiatomic single-phase solid solutions and show a greater value of deformation of the crystal lattice and stress after irradiation compared with pure vanadium. It has been proposed that increasing the number of elements in the V-Nb-Ta-Ti system reduces the mobility of defects created by irradiation, which leads to the formation of smaller clusters and an increase in microdeformation.