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In this study, a high-entropy alloy (HEA) of Al–Co–Cr–Fe–Ni system was fabricated via wire-arc additive manufacturing technology (WAAM) in the atmosphere of pure Ar followed by high-intensity electron beam treatment. SEM, TEM, and X-ray diffraction methods were used to characterize the manufactured material's microstructure. The HEA has the following composition: Al (36.5 at. %), Ni (33.7 at. %), Fe (16.4 at. %), Cr (8,6 at. %) and Co (4.9 at. %). The obtained material without electron beam treatment has a polycrystalline structure with a grain size of 4–15 μm. Bulks of grains are enriched in Al and Ni, while grain boundaries contain Cr and Fe. Co is quasi-uniformly distributed in the crystal lattice of the manufactured HEA. The ultimate material strength in testing for compression depends on production mode and varies within the interval from 652 to 1899 MPa. The HEA wear parameter amounts to 1.4∙10−4 mm3/N∙m, friction coefficient - 0.65. In testings for tension, the material failure occurred by the mechanism of intragrain cleavage. The formation of brittle cracks along boundaries and in grain boundary junctions, i.e. in sites containing the inclusions of second phases, is revealed. The HEA's irradiation by a pulsed electron beam with the energy density of 10–30 J/cm2 (pulse duration 200 μs, number of pulses 3) results in material homogenization, decreased crystal lattice microdistortions, and an increase in sizes of coherent scattering regions. High-velocity crystallization of the molten surface layer of HEA samples is accompanied by columnar structure formation having a submicro-nanocrystalline structure.

The quantitative estimation of strengthening mechanisms of rails’ surface layer is carried out on the basis of regularities and formation mechanisms of structure-phase states revealed by the methods of modern physical materials science. It is performed at different depth of rail head along central axis and fillet of differentially quenched 100-m rails after extremely long-term operation (gross passed tonnage of 1411 mln. tons). The contributions caused by the matrix lattice friction, intraphase boundaries, dislocation substructure, presence of carbide particles, internal stress fields, solid-solution strengthening of pearlite component of steel structure were estimated. It is shown that in the surface layer the main mechanism of strengthening is due to the interaction of moving dislocations with low-angle boundaries of nanometer dimensional fragments and subgrains. In a near-surface layer at a depth of 2–10 mm the main dislocation strengthening mechanism is due to interaction of moving dislocations with immobile ones.

The aim of the study is to elaborate an econometric model to determine the conditions for ensuring the balanced development of environmental, economic, and social components of the Russian agricultural sector within the Eastern European region. The method of fuzzy sets was used to build an integral model for assessing the level of sustainable development of the agricultural sector in Eastern Europe on the basis of economic, environmental, and social sustainability indicators. The control indicators (independent variables) and integral economic, environmental, social sustainability (dependent variables) helped build multifactor linear regression models and calculate the indicators of elasticity of dependent variables from independent variables, which characterize the change in sustainable development indicators with the growth of controlling factors by 1%. This model allows us to define and analyze the levels of sustainable development of the industry, both in a specific country and within the region in general. The study shows that, for Russia and Eastern European countries, innovation is one of the crucial factors in ensuring sustainable development of agriculture in the region, taking into account the current state and level of economic development.

The study is aimed at determining the oscillators of crisis manifestations when the Russian economy tries to make transition to the path for accelerating technological development and forming an innovative economy. Short-term cycles were determined in the development of the Russian economy from 1995 to the first half of 2020 through the Fourier spectral analysis. Using the Granger test, causal relationships between the leading indicators of the economic crisis and the real GDP index in Russia were identified and substantiated. They reflect the influence of the key rate dynamics on the volume of lending, savings, investments, the yield on securities and the exchange rate; volumes of bank loans per the share of non-performing and bad loans and innovative development of the economy. Based on the constructed neural models of the oscillator influence on the level of real GDP in Russia, it was determined that the rapid growth of bank and mortgage lending, the devaluation of the ruble, a decreased volume of gross foreign investment and the level of innovative development predetermine crisis manifestations in the national economy. The lags of the influence of changes in the leading indicators of the economic crisis on the development of the economy were calculated. The results obtained can contribute to the effectiveness of the anti-crisis regulation strategy in Russia. They can serve as a basis for increasing the efficiency of long-term innovative development and creating appropriate conditions for increasing the scientific and technological potential of the country.