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Документ A study of an effect of the parameters of niobium-based ion cleaning of a surface on its structure and properties(PC тесhnology сеntеr, 2017) Postelnyk, H. O.; Knyazev, S.; Meylekhov, A. A.; Stolbovoy, V. A.; Kovteba, D. V.The paper describes using techniques of structural engineering in a comprehensive study of the effects of the negative displacement potential, nitrogen and argon pressures, as well as the distance from a sample to the cathode on the processes of sputtering and depositing. In practice, it is highly important to obtain steel surfaces with high mechanical properties and low roughness. The highest microhardness is manifested at the highest degree of sputtering on the samples at Ub=–1,300 V. It has been determined that the presence of nitrogen in the vacuum chamber shifts the equilibrium point of sputtering and depositing towards a higher Ub. It has been established that the presence of argon in the ion bombardment process increases the sputtering rate, whereas the presence of active nitrogen gas reduces the deposition rate due to nitride formations on the surface. The point “sputtering-depositing” shifts: in the case of Ar (from Ub=–350 V to Ub=–200...–300 V) when the RN increases from 0.002 Pa to 0.66 Pa, respectively. In the case of nitrogen, when PN increase from 0.02 Pa to 0.08 Pa, the point shifts from Ub=–400 V to Ub=–600 V (at a distance of 300 mm from the cathode to the sample).Документ Formation of Superhard State of the TiZrHfNbTaYN Vacuum–Arc High-Entropy Coating(Allerton Press, Inc., 2018) Beresnev, V. M.; Sobol, O. V.; Andreev, A. A.; Gorban, V. F.; Klimenko, S. A.; Litovchenko, S. V.; Kovteba, D. V.; Meilekhov, A. A.; Postelnyk, A. A.; Nemchenko, U. S.; Novikov, V. Yu.; Maziilin, B. A.Complex studies of the formation of the superhard state in the TiZrHfNbTaYN vacuum-arc high-entropy coating were carried out. Based on the approach of the structural surface engineering, the regularities of the formation of the triads composition–structure–physico-mechanical properties depending on the supplied potential displacement are established. It is shown that the increase of Ub at the formation of a coating leads to a decrease of the relative content of a light (Ti) and increase of a heavy (Ta, Hf) metal components, which is determined by radiationally stimulated processes in a near surface region at the deposition. The formation of the single-phase state (based on the fcc of metal lattice) in the range Ubfrom –50 to –250 V and revealed the formation of the preferred orientation of the crystallites with the axis [111], which is perpendicular to the growth plane. The increase of the perfection of the texture with the [111] axis with increasing Ub is accompanied with an increase of the coatings hardness, which makes it possible to achieve the superhard state (H = 40.2 GPa) at Ub = –250 V.Документ Changes in the structural state and properties of vacuum-arc coatings based on high-entropy alloy TiZrHfNbTa under the influence of nitrogen pressure and bias potential at deposition(2018) Sobol, O. V.; Andreev, A. A.; Mygushchenko, R. P.; Gorban, V. F.; Stolbovoy, V. A.; Meylekhov, A. A.; Subbotina, V. V.; Kovteba, D. V.; Zvyagolsky, A. V.; Vuets, A. E.Complex studies have been carried out on the effect of nitrogen pressure and the negative bias potential on the structure and properties of vacuum-arc nitride coatings based on the high-entropy alloy TiZrHfNbTa. It is defined that the change in pressure during deposition (in the range 0.01...4 mTorr) mainly affects the nitrogen atoms content in the coating. The feed of a negative bias potential to the substrate (Ub = -50...-250 V) makes it possible to control the content of the metallic component using the effect of selective sputtering of atoms in the formation of coatings. Determined, that as the pressure increases the structural state associated with the predominant growth orientation (axial texture) of the crystallites changes. The texture changes in the sequence [311] → [311] + [111] → [111] with increasing pressure for a six-element (TiZrHfVNbTa)N nitride and the texture state changes in the sequence [110] → [110] + [111] → [111] for a five-element (TiZrHfNbTa)N nitride. It is shown that the presence of a bi-textured state in the coating makes it possible to achieve an ultrahard state with a hardness exceeding 50 GPa.