The paper offers the measuring results for hydrogen permeability of the membranes made of 40 μm thick tantalum foil covered with a metallic film with different thicknesses on one side. The measurements were performed when the membranes were in contact with a commercial argon and hydrogen gases mixed at the ratio of 1/5 at an overpressure of 500 kPa and at 580-585°C. It is shown that films of Mo, Re, W, Cu, Co, and Ni metals deposited on the tantalum membrane surface from the side facing a hydrogen-containing gas mixture increase its hydrogen permeability. The effect degree of these metals increases in the specified row from left to right. The effect on the hydrogen permeability of tantalum membranes, comparable to and superior to the deposition of a Pd film, exerts the deposition of Cu, Co, and Ni films. It is explained by the high hydrogen permeability level of these metals and the catalytic activity of their surface that results in intense hydrogen dissociation. The value of the hydrogen permeability of the membranes naturally increases with a thickness decrease of metallic films, however, it is obvious that this behavior is not linear. The hydrogen permeability of membranes with Cu, Co, and Ni films decreases over time, that is explained by the oxygen segregation at the Ta membrane/film interface, as well as by the processes on the membrane surface in contact with the gas mixture. The nature of these processes should be studies since the lower oxides of these metals are reduced by hydrogen at this temperature.

Purpose: The main goal of the work was to find the interconnection between the high-frequency magnetron sputtering parameters and the adhesion properties of CaP coatings formed on the surface of titanium substrate. Methods: Calcium-phosphate coatings, similar in composition to hydroxyapatite, were generated by high-frequency magnetron sputtering on titanium substrate at different values of high-frequency specific power over times of one and two hours. Afterwards, the generated coatings were studied using the method of X-ray phase analysis, and sclerometric tests (scratch test) were carried out. The adhesion strength of the deposited coatings was tested for different coating thicknesses from 0.45 to 1.1 × 10–3 mm. Results: According to the results of sclerometry, it was found that with an increase in the high-frequency specific power of plasma to 3.15 W/cm2, the adhesion strength of the calcium-phosphate coating also increases. For all the coatings, the critical loads at which the coating completely exfoliated from the substrate were determined. Conclusions: According to the research results, the most optimal conditions for obtaining high-adhesive calcium-phosphate coatings were determined.

The research represents a newly-developed simple method to apply hydroxyapatite by gas-dynamic spraying. The hydroxyapatite coating formed on VT1-0 titanium were obtained following the mechanochemical interaction of hydroxyapatite and titanium with gas-dynamic spraying. The article proposes the phase composition, surface morphology, and roughness of these coatings. The surface morphology of the hydroxyapatite coating had a porous structure. The transverse sections of coatings were researched to study the interaction of hydroxyapatite with a titanium base. It was shown that the coatings mainly form in the titanium bedding depressions. Analyzing the roughness parameter Ra of hydroxyapatite coatings made it possible to conclude that the samples obtained fell almost within the same limits. These data are within the roughness optimum (Ra = 2-3 μm) of artificial surfaces aimed to manifest the best human osteogenic properties. The analyzed phase composition enabled to establish the fact that the hydroxyapatite layer composition does not change significantly after spraying that is important for biomedical use.

Metal parts in machinery often fail as a result of damage caused by wear and tear, resulting in the loss of functionality of the products. Thin film solid nitride coatings are used to improve the wear resistance and service life of parts and are considered to be effective. The article presents a brief overview of modern literature in the field of obtaining wear resistant coatings of titanium carbonitride by using magnetron sputtering. The review presents a detailed assessment of the scientific results obtained depending on the deposition parameters and the conditions for obtaining coatings. The results of the coefficient of friction, wear rate of the coating and counterbody, nanohardness and adhesion force of coatings obtained by magnetron sputtering and its modifications are shown. The influence of alloying elements on the mechanical and tribological properties of titanium carbonitride coatings is considered. Recent advances in the production of titanium carbonitride coatings with improved wear characteristics are discussed.

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