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The purpose of the research was to form a Ti-Ta-N- system bioinert coating on Ti6Al4V alloy surface as well as to study its structure and properties. The main contribution of the research is in the following. Electro-explosion spraying of tantalum coating on VT6 titanium alloy surface was pioneered in the research. After that the processing of the coating by low-energy high-current electron beam and subsequent nitriding was carried out in a single technological cycle. It has been established that a nanocrystalline coating based on tantalum, nitrogen and titanium was formed as a result of the technological operations. The phase composition of the coatings has been detected. The variations in crystal lattice parameters being formed in coating of phases and coherent scallering regions of these phases depending on power density of electron beam have been determined. Structural characteristics of the coatings at nano- and microlevel have been detected. Tests of coatings for nanohardness, the Young modulus, wear resistance and friction factor have been carried out. By all technical characteristics Ti-Ta-N-system coating exceeds titanium of VT6 grade. The cause of the increase in mechanical characteristics of the Ti-Ta-N-system coating is their nanostructural state and strengthening phases. Tests for proliferation activity of fibroplasts and antimicrobial activity have shown better results in comparison with VT6 titanium alloy as well. It is due to escape of vanadium ions from VT6 alloy into nutrient cell medium and their destructive effect on cell cultures. Variations in proliferation and antimicrobial activity develop due to amplification of cell proliferation. A complex of the obtained characteristics makes it possible to recommend Ti-Ta-N-system coating for its application as a bioinert coating on different implants in furure.

The application of electron-beam processing enabled to obtain the mirror luster of electroexplosive coating surface of CuO-Ag system, to reduce the roughness without the loss of the composite material, to homogenize the surface layer of the coatings to the whole thickness of the coating being equal to 40 μm. The utilization of the selected regimes of pulsed electron—beam processing results in the realization of the processes of surface layer structurization of electroexplosive coating of CuO-Ag system. The phase composition of electroexplosive coating of CuO-Ag system after electron—beam processing presents the following phases: Ag, Cu2O, Cu64O and Cu. The electroexplosive coating of CuO-Ag system fail after 3000 cycles of switching on / switching off in the course of the accelerated electroerosion resistance tests. During the accelerated electroerosion resistance tests the electrical resistance is acceptable to the weak—current electrical contacts and is within the interval from 5.8 to 14.8 μOhm. The wear resistance tests have shown that EES of copper is accompanied by ≈3.3-fold increase in wear resistance of the modified layer; in this case, ≈1.3-fold increase in the fiction coefficient is observed. Nanohardness of coating layer varies within 280 MPa to 290 MPa at the average hardness value being 866.5 MPa. Young modulus varies within 24.3 GPa to 71.7 GPa at the average value of the modulus of 49.6 GPa.

For the first time, electroerosion-resistant coatings of the CuO–Ag system were obtained by electro-explosive spraying. The coating structure was investigated by atomic force microscopy and scanning electron microscopy. The formed coating is a homogeneous composite material consisting of a silver matrix and CuO inclusions located in it. The composite electro-explosive coating of CuO–Ag system is obtained on copper electric contact of contactor KPV-604. Tests of sprayed coatings for electrical erosion resistance under arc erosion conditions were carried out. A formation mechanism of hierarchical levels of the structure of electro-explosive coatings was suggested. The mechanism is based on theoretical concepts of the formation and evolution of fractal aggregates with diffusion-limited and cluster-cluster aggregations of the CuO. Based on the electrical properties of silver and copper oxide, the dependence of electrical contact resistance on the number of on/off cycles in the process of testing for electrical erosion resistance is substantiated.

This paper presents a brief review of research made by the authors to determine feasibility of using a titanium-based bilayer material in industrial applications. One layer, corrosion preventive, is formed by surface alloying with highly corrosion-resistant doping elements, in particular, Ta, Nb and Zr. These elements have significantly higher corrosion resistance than titanium. Applying them on the titanium substrate allows formation of a coating resistant, in particular, to boiling strong acids. Resistance of obtained coatings in said media is many times higher than that of titanium or stainless steel. The coatings are formed using a high-penetration electron beam ejected to the atmosphere. This article contains references to findings of previous works and offers some new data.

This paper presents the results of structural investigations and results of tribological and microhardness tests of the coating obtained by electron beam cladding of a Ni-Cr-Si-Fe-B self-fluxing alloy on low-carbon steel. After electron beam treatment high-quality dense layer with a thickness of 1.2-1.8 mm was obtained. The structure of the coating consisted of dendrite crystals based on y-Ni-solid solution and eutectic with complex composition. Microhardness of the coating achieves 370 HV. Wear-resistance of the coating obtained by electron-beam cladding technique was 1.6-fold higher than that of low-carbon carburized steel.

The structure and microhardness of surface layers, obtained by non-vacuum electron beam cladding of Ti-Mo-C powder mixture on a steel substrate after different types of heat treatment, were investigated. After cladding samples were heat treated in a furnace at 200...500 °C, as well as quenched at 860 ° C and then underwent high-temperature tempering. Heat treatment of cladded coatings induced tempering of martensite and precipitation of cementite particles (Fe3C). Transmission electron microscopy of the samples after heating and holding at 300 ° C revealed precipitation of nanosized cubical TiC particles. The formation of hard nanosized particles led to the surface layer microhardness growth. The highest level of microhardness (which was 1.2...1.5-fold higher in comparison with coating microhardness after heat treatment) was achieved after heating of the claded material at 300 °C and 400 °C Additional quenching of samples at 860 °C did not increase the microhardness level.