Effect of irradiation by nitrogen and helium ions on the structure and electrical resistance of nanocrystalline V-N coatings

The results of studies of the radiation damage of V-N coatings irradiated by nitrogen and helium ions with energies of 40 and 20 keV, respectively, are presented. The coatings have been obtained using a technique of ion-stimulated deposition and represented a nanocrystalline composite with grain sizes of 20-50 nm, intergrain junctions of which contained voids with sizes of 3-6 nm. It has been shown that during irradiation, the electrical resistivity of such objects increases. No visible structure changes are observed up to doses of 7-8 x 10(16) ion/cm(2). A further increase in the dose leads to changes in the void structure and to a transformation of the closed porosity to an open one. It has been shown that the system of arising channels creates conditions for evolving the accumulating helium and preserving the integrity of the coating.