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Samples of composite materials based on BrAMts9-2 bronze with the introduction of the Udimet500 and Inconel625 nickel alloys were obtained by wire-feed electron-beam technology. The studies show that the structures of composites formed during printing, although fairly similar due to the same base of the alloys, have different features due to different combinations of alloying elements. The mechanical properties of the samples with the introduction of up to 15 % of the Udimet500 alloy are higher than those of the samples of the second material. With the introduction of 25 % of a nickel alloy, the strength is higher for the composite material samples with the introduction of the Inconel625 alloy. The microhardness of the samples with the introduction of 5 % of a nickel alloy is identical, the introduction of large volumes of a nickel alloy leads to the implementation of greater hardness in the samples with the introduction of the Inconel625 alloy due to the higher content of refractory materials. Relative elongation after rupture varies insignificantly for the samples of both types.

Introduction. The current state of the art in the field of hard coatings application requires the formation of nanostructured compositions using different chemical elements. Modern hard coatings are able to combine different properties such as high hardness, wear resistance, corrosion resistance. At present, coatings formed by layer-by-layer deposition of zirconium and chromium nitrides are promising. When depositing combinations of chemical elements on various substrates, studies are required aimed at investigating its microstructure and, mainly, residual stresses formed during the deposition of multilayer coatings. The purpose of this work is to investigate the structural-phase state and residual stresses of ZrN/CrN system coatings formed by plasma-assisted vacuum-arc method from the gas phase. Research methods. Samples with coatings of zirconium and chromium nitrides deposited on substrates of hard alloy VК8 are investigated. Transmission electron microscopy is used to study the microstructural characteristics of multilayered coatings and X-ray diffraction analysis is used to quantify macroscopic stresses. Results and discussion. Based on the experimental results obtained it is found that changing the modes of deposition of multilayer ZrN/CrN coatings with regard to rotation speeds of table and substrate holder leads to variations in microstructure, morphology and internal stresses of surface layers of multilayer coatings. It is shown that by changing conditions for the multilayer coating deposition the possibilities of forming ZrN/CrN coatings on the substrate made of VK8 alloy with nanoscale thickness of coating layers open up. X-ray diffraction analysis indicates mainly insignificant stresses, and at high table and substrate rotation speeds – high compressive stresses in the multilayer coating. Transmission electron microscopy revealed that CrN and ZrN coatings have a common multilayer coating growth texture at low rotation speeds, and at high speeds a textural misorientation of the phases of the coating layers is observed. Based on the results obtained it is possible to recommend coatings of ZrN/CrN system as hard coatings.

Electron beam additive manufacturing from dissimilar metal wires was used to intermix 5, 10 and 15 vol.% of Ti-Al-Mo-Z-V titanium alloy with CuAl9Mn2 bronze on a stainless steel substrate. The resulting alloys were subjected to investigations into their microstructural, phase and mechanical characteristics. It was shown that different microstructures were formed in an alloy containing 5 vol.% titanium alloy, as well as others containing 10 and 15 vol.%. The first was characterized by structural components such as solid solution, eutectic intermetallic compound TiCu2Al and coarse grains of γ1-Al4Cu9. It had enhanced strength and demonstrated steady oxidation wear in sliding tests. The other two alloys also contained large flower-like Ti(Cu,Al)2 dendrites that appeared due to the thermal decomposition of γ1-Al4Cu9. This structural transformation resulted in catastrophic embrittlement of the composite and changing of wear mechanism from oxidative to abrasive.

Introduction. Friction stir welding and processing are almost identical processes of severe plastic deformation at elevated temperatures. These technologies differ mainly in the purpose of its use: the formation of a hardened surface layer or producing a welded joint. However, it is known that both during welding and during processing of heavy gauge workpieces temperature gradients occur. As a result, the conditions of adhesive interaction, material plastic flow, and the formation of the stir zone change as compared to thin-sheet workpieces with fundamentally different heat dissipation rates. In this connection, the purpose of the work is to determine the regularities of the structure formation and stability of the mechanical properties in different directions in the material of 35-mm-thick aluminum-magnesium alloy samples produced by friction stir welding/processing. Research Methodology. The technique and modes of friction stir welding and processing of AA5056 alloy workpieces with a thickness of 35 mm are described. Data on the equipment used for mechanical tests and structural research are given. Results and discussion. The data obtained show the excess mechanical properties of the processing zone material over the base metal ones in all studied directions. Material structure heterogeneities after friction stir welding/processing of heavy gauge workpieces have no determining effect on the stir zone properties. At the same time, there is no clear correlation between the tensile strength values and the load application direction, nor is there any significant difference in mechanical properties depending on the location of the samples inside the stir zone. The average ultimate tensile strength values in the vertical, transverse, and longitudinal directions are 302, 295 and 303 MPa, respectively, with the yield strength values of 155, 153 and 152 MPa, and the relative elongation of 27.2, 27.5, 28.7 %.

This study presents the results of experimental work on the production and examination of samples of laminated polymetallic products made by wire-feed electron-beam additive technology using the technique of controlled filament feeding into the melt bath. The structure of the products based on M1 copper and AMg5 aluminum alloy combines metallic and intermetallic layers with the presence of a gradient transition between the phases. Inside the layers with a transition structure the distribution of intermetallic phases can be of different types. The microhardness values of the different structural constituents of the samples differ by more than a factor of 16. The mechanical properties of the material of the transition layers are characterized by low strength and low plasticity. In the structure of the intermetallic layers and at the boundary between them the formation of defects in the form of cracks and delaminations is observed.

This paper is devoted to using multi-pass friction stir processing (FSP) for admixing 1.5 to 30 vol.% copper powders into an AA5056 matrix for the in situ fabrication of a composite alloy reinforced by Al-Cu intermetallic compounds (IMC). Macrostructurally inhomogeneous stir zones have been obtained after the first FSP passes, the homogeneity of which was improved with the following FSP passes. As a result of stirring the plasticized AA5056, the initial copper particle agglomerates were compacted into large copper particles, which were then simultaneously saturated by aluminum. Microstructural investigations showed that various phases such as α-Al(Cu), α-Cu(Al) solid solutions, Cu3Al and CuAl IMCs, as well as both S and S’-Al2CuMg precipitates have been detected in the AA5056/Cu stir zone, depending upon the concentration of copper and the number of FSP passes. The number of IMCs increased with the number of FSP passes, enhancing microhardness by 50–55%. The effect of multipass FSP on tensile strength, yield stress and strain-to-fracture was analyzed.

In the present work, the products in the form of vertical walls were made of heat-resistant nickel-based superalloy ZhS32 via the method of electron beam additive technology. Unidirectional printing strategy was applied. The effect of heat input and 3D printing strategy on the macrostructure, dimensions, and morphology of microstructure elements was established. It was shown that the additive product material has a directed macrostructure. The only exclusion was the final layer with a thickness of no more than 3.5 mm. The directed macrostructure consisted of dendrites oriented predominantly along the crystallographic direction {001} of the primary dendrite arms. The misorientation of the dendrite axes did not exceed 9 degrees. The angle between the predominant dendrite growth direction and the normal to the substrate was 23 degrees. The average primary dendrite arms’ spacing increased monotonically from 16 µm at 5 mm from the substrate to 23 µm in the final layers of the product material (the overall height was 41 mm). It was found that the average size of γ’ (Ni3Al)-phase precipitations in the form of nanoscale and submicrocrystalline cuboids varied in the range of 76 to 163 nm depending on the distance from the substrate. The size of γ’-phase precipitations reached a maximum at about 30 mm from the substrate, while in the final layers of the product material, the average cuboid size did not exceed 135 nm. Extreme dependence of the size of γ’-phase precipitations on the height of the product followed from a combination of a given monotonic decrease in heat input and heat accumulation in the product material as it formed, as did additional heat removal by means of radiation during formation of the final layer of the product without re-melting. Chemical elements of the austenitic steel substrate material were not detected in the product material more than 8 mm from the substrate. There were no macrodefects, such as voids, in the entire volume of the product material.

Novel composite CuA19Mn2/Udimet-500 alloy walls with different content of the Udimet 500 were built using electron-beam double-wire-feed additive manufacturing. Intermixing both metals within the melted pool resulted in dissolving nickel and forcing out the aluminum from bronze. The resulting phases were NiAl particles and grains, M23C6/NiAl core/shell particles and Cu-Ni-Al solid solution. Precipitation of these phases resulted in the increased hardness and tensile strength as well as reduced ductility of the composite alloys. Such a hardening resulted in improving the wear resistance as compared to that of source aluminum bronze.

Multi-pass friction stir processing (FSP) was used to obtain a titanium alloy/copper hybrid composite layer by intermixing copper powder with a Ti6Al4V alloy. A macrostructurally inhomogeneous stir zone was obtained with both its top and middle parts composed of fine dynamically recrystallized α- and β-Ti grains, as well as coarse intermetallic compounds (IMCs) of Ti2Cu and TiCu2, respectively. Some β grains experienced β → α decomposition with the formation of acicular α-Ti microstructures either inside the former β-Ti grains or at their grain boundaries. Both types of β → α decomposition were especially clearly manifested in the vicinity of the Ti2Cu grains, i.e., in the copper-lean regions. The middle part of the stir zone additionally contained large dislocation-free β-Ti grains that resulted from static recrystallization. Spinodal decomposition, as well as solid-state amorphization of copper-rich β-Ti grains, were discovered. The FSPed stir zone possessed hardness that was enhanced by 25% as compared to that of the base metal, as well as higher strength, ductility, and wear resistance than those obtained using four-pass FSPed Ti6Al4V.

The paper investigated the possibility of obtaining large-sized blocks of C11000 copper on stainless steel substrates via electron beam wire-feed additive technology. The features of the microstructure and grain texture formation and their influence on the mechanical properties and anisotropy were revealed. A strategy of printing large-sized C11000 copper was determined, which consists of perimeter formation followed by the filling of the internal layer volume. This allows us to avoid the formation of defects in the form of drops, underflows and macrogeometry disturbances. It was found that the deposition of the first layers of C11000 copper on a steel substrate results in rapid heat dissipation and the diffusion of steel components (Fe, Cr and Ni) into the C11000 layers, which promotes the formation of equiaxed grains of size 8.94 ± 0.04 μm. As the blocks grow, directional grain growth occurs close to the orientation, whose size reaches 1086.45 ± 57.13 μm. It is shown that the additive growing of large-sized C11000 copper leads to the anisotropy of mechanical properties due to non-uniform grain structure. The tensile strength in the opposite growing direction near the substrate is 394 ± 10 MPa and decreases to 249 ± 10 MPa as the C11000 blocks grows. In the growing direction, the tensile strength is 145 ± 10 MPa.

In the present work, the tribological experiments on sliding the electron beam composite M2+WC coating have been carried out with characterization of the sample microstructures and phases both before and after the testing using metallography, SEM, EDS, and XRD. The sliding in the speed range 0.8–3.6 m/s resulted in simultaneous reduction in both wear rate and coefficient of friction with the sliding speed. Investigations showed that such a tribological adaptation was due to the tribochemical generation of lubricative FeWO4 and Fe2WO6 mixed oxides and the generation of a mechanically mixed composite layer on the worn surfaces that consisted of carbide fragments, an oxidized metal matrix, and was lubricated by in-situ formed mixed iron-tungsten oxides.

In the presented work, the effect of friction stir processing admixing the zirconium tungstate ZrW2O8 powder on the microstructure, mechanical and tribological properties of the AA5056 Al-Mg alloy stir zone has been studied. The FSP resulted in obtaining dense composite stir zones where α-ZrW2O8 underwent the following changes: (i) high-temperature transformation into metastable β’-ZrW2O8 and (ii) decomposition into WO3 and ZrO2 oxides followed by the formation of intermetallic compounds WAl12 and ZrAl3. These precipitates served as reinforcing phases to improve mechanical and tribological characteristics of the obtained fine-grained composites. The reduced values of wear rate and friction coefficient are due to the combined action the Hall–Petch mechanism and reinforcement by the decomposition products, including Al2O3, ZrO2, β’-ZrW2O8 and intermetallic compounds such as WAl12 and ZrAl3. Potential applications of the above-discussed composites maybe related to their improved tribological characteristics, for example in aerospace and vehicle-building industries.

The results of a study of the autonomous regulation of the heart rate in elite wrestlers with different dominance of the cerebral hemispheres were present in the manuscript 23 elite wrestlers. Were examined members of the National Team of Ukraine in Greco-Roman wrestling, aged 22-34 years-old. A body composition monitor "Omron BF511" and a computer electrocardiograph "Fazagraf" were used. It was revealed that elite wrestlers with a dominance of the right hemisphere have more intense regulation of the heart rhythm compared to wrestlers with a dominance of the left hemisphere of the brain. With an increase in the tension of the system of autonomous regulation of the heart rhythm in wrestlers with the dominance of the right hemisphere of the brain, the activation of the central and sympathetic division of regulation occurs. For the purpose of a more effective preparation process and in the development of individual training programs for elite wrestlers, it is necessary to determine the dominance of the cerebral hemispheres.

The article is devoted to the study of problematic issues of ensuring environmental safety in the Russian Federation as an urgent task of the state and society, on the solution of which the national security of the country and the possibility of its sustainable development largely depend. The role and importance of environmental safety in the system of national security of Russia is analyzed, the necessity of forming and implementing a long-term state policy in the field of environmental protection and rational use of natural resources is proved. On the basis of environmental monitoring data, the current state of the environment is characterized, especially in areas of intensive industrial production (the Urals, Siberia, the Arctic), negative anthropogenic factors are identified that violate the ecological balance in the territories of active resource extraction, and the environmental threats arising in this connection are analyzed. It is noted that in the context of increasing economic activity and global climate change, compliance with environmental safety requirements becomes a factor capable of ensuring sustainable economic development.

The authors analyze the problems of digitalization of education in Russia. Realizing that the widespread introduction of information and communication technologies in educational activities is dictated by the need to train new qualified personnel for the labor market in the digital economy, the authors at the same time draw attention to the possible negative consequences of this process. In their opinion, the use of digital technologies in the educational process, in addition to the undoubted advantages, which are the expansion of the resource of educational information, the ability to use educational content at a convenient time and in a convenient manner, the ability to build individual educational paths, improve educational system management tools, etc., can contribute and a decrease in the quality of education, since it changes the mechanisms of perception of information, without forcing a person to think creatively and reducing his communication skills.The digitalization of education in Russia is constrained by technical and legal problems. The main ones are: the absence in Russian educational legislation of a clear distinction between the basic concepts: "e-learning", "information technology", "distance educational technologies", "information and educational environment"; lack of a regulatory framework governing the use of e-learning, distance learning technologies; lack of standards for the provision of educational services using these technologies; the spontaneous nature of the introduction of digital technology in the educational process; most teachers lack the necessary skills to work in a digital environment.In addition, distance education in the Russian Federation does not have the legal status of an independent form of education, which is a limiting factor for the digitalization of education in general. The authors conclude that the digitalization of the educational process in Russia is impossible without solving these problems and offer a number of specific recommendations in this area.

The article deals with the basic tendencies in higher education in Russia. It is emphasized that the notion innovativeness in education should not be interpreted only in connection with new teaching modes, as it includes innovative objectives and educational syllabus, except using innovations. It is shown that a complex and integrated understanding of innovativeness helps to reform Russian education in line with the demands of the information-oriented society. Three basic ways for the innovative development of the higher education in Russia are given: 1. the realization of the competence-based model in vocational training; 2. the use of information technologies in education; 3. the creation of innovative educational institutions aiming innovative development. Active and interactive teaching methods used in higher education are characterized. The peculiarities of cross-disciplinary integration are identified. The article gives an analysis of the reasons of underdevelopment of information technologies of innovational educational institutions organization.

The article deals with the current trends in educational development in Russia in the context of the reforming. The aim of the Europeanisation of Russian education is analyzed from different points of view. Reforming is a trait of educational globalization, causing the integration of educational systems. It is also a part of Russian officials’ policy. In case of the unification of Russian educational standards with the European ones, education in Russia will probably become one of the world-leading. The article states that the new educational trends and reforming are caused by the process of educational globalization. The article gives an analysis of the negative implications of globalization which should be limited to some part to save national identity. The article reviews some peculiarities of the implementation of the Bologna Process in Russia. Critically judging current educational tendencies, the authors offer an alternative way to the reforming of Russian educational system.

The article is devoted to the study of the peculiarities of the formation of health protection institutes in Russia and European countries. Their importance for the current state of health systems is analyzed from the standpoint of historical and socio-legal analysis. The authors note that the formation of an administrative mechanism for the prevention and control of diseases took place in Eastern and Western Europe throughout the Middle Ages and New Times. However, the turning point in the development of health care institutions in Russia and in Europe was the 18th century. Since that time, we can talk about the formation of health systems in the modern sense. According to the authors, the idea of the state responsibility for the health of its population, as well as the belief of European scientists about the social nature of many diseases, which spread in Western Europe, contributed to this formation. In the authors’ opinion, this fact led to the emergence of the first health laws, in which the main factor in the health of citizens was recognized as an improvement in their living conditions. It is noted that international recognition of health as a subjective right of every person has led to revolutionary changes in national health systems. National health standards began to change in the direction of their compliance with international standards. According to the authors, there are legal prerequisites for the formation of an effective and socially-oriented health care system in Russia. The authors think that there are legal prerequisites for the formation of an effective and socially-directed health care system in Russia. This is due to the constitutional consolidation of the right to health protection, as well as the treatment of health in its international legal significance. The main methods used were the method of analysis, the rationale, the comparative-historical method.

The article is a comprehensive study of the problems of legal provision of environmental safety in the Russian Federation. The work of the authors was built taking into account the insufficient formation of the legal institution of environmental safety in Russian environmental law. This necessitated the use of an interdisciplinary approach, which allows us to fully consecrate the issues studied. The authors draw attention to the fact that initially environmental safety was not considered by Russian legislators and scientists as an integral part of national safety. The authors conclude that the inclusion of measures designed to ensure environmental safety in a single system for ensuring national safety should contribute to their improvement and development, since they are now becoming a priority. At the same time, the authors note the problem of the terminological inconsistency of the main strategic documents in this area - the National Safety Strategy of the Russian Federation and the Strategy of Ecological Safety of the Russian Federation for the period up to 2025, which, in their opinion, may negatively affect the effectiveness of legal support for environmental safety in Russia.

The article is a study of the process of formation of the organizational and legal mechanism for ensuring environmental safety in the Russian Federation, as well as an analysis of a number of urgent problems arising in the implementation of the state environmental policy by the country. The authors’ study is interdisciplinary in nature and includes not only a legal analysis of regulatory acts adopted by the Russian state in order to ensure environmental safety, but also some assessments of an economic and natural-scientific (environmental) nature related to the functioning of resource-extracting sectors of Russian industry and their impact on state of the environment. Considerable attention is paid to the worldview aspects of the topic under study. The role of the territories of the Russian Federation not disturbed by economic activity in maintaining the sustainability of the global ecosystem is emphasized.

The article is devoted to the analysis of problems of maintenance of ecological safety of the mining enterprises. The aim of the work was the formulation of proposals, the implementation of which, in the opinion of the authors, is capable of raising the level of environmental safety of the mining industry and ultimately ensuring the environmentally oriented growth of the Russian economy.