The structure and properties of the surface of a plasma-deposited layer in a nitrogen environment of high-speed molybdenum steel on a substrate of medium-carbon steel grade 30KhGSA were studied using modern physical materials science methods. The deposited layer was irradiated with pulsed electron beams with the following parameters: energy density of 30 J/cm², duration of one exposure of 50 μs, frequency of 0.3 Hz, number of pulses of 10. In the initial state, the surface layers contain a polycrystalline structure of the dendritic type with a non-uniform distribution of molybdenum, chromium, aluminum, nitrogen and oxygen, surrounded by a developed network of ledeburite eutectic. The relative content of elements (except for Mn, C and O₂) decreases as it approaches the substrate. The microhardness of the deposited layer is 5.6 MPa, which increases to 6.2 MPa after a single high-temperature tempering, and to 7.2 MPa after a double tempering. Electron-beam pulsed action performed after a double high-temperature tempering modifies the structure and properties. A quasi-homogeneous distribution of alloying elements, the formation of a fine-grained structure with a grain size of 4 ‒ 6 μm, in the volume of which lamellar martensite was found, were revealed. The previously formed structure of dendritic crystallization is not observed. The microhardness of the deposited layer after electron-beam treatment increases and reaches 8.7 MPa, which is almost 2 times higher than the microhardness of the substrate. The revealed patterns of change in nanohardness and Young's modulus from the distance to the irradiation surface confirm the developed ideas about the nature of hardening of the plasma deposited layer of high-speed molybdenum steel.

The technology of plasma surfacing in nitrogen on 30HGSA grade steel with a powder wire of the MoCrCoC system with a diameter of 4 mm formed a deposited layer with a thickness of approximately 9 ‒ 10 mm Argon of the highest grade was used as the plasma-forming gas. The structural and phase states and defective substructure of the surface of a plasma-deposited layer in a nitrogen medium with high-speed molybdenum steel on a substrate subjected to double tempering at a temperature of 560 ‒ 580 °C for 1 hour have been studied by methods of modern physical materials science. It is shown that the deposited layer has a polycrystalline structure and contains layers of eutectic. The formation of a multiphase structure in the deposited layer was revealed, represented by an α-phase (solid solution based on the BCC crystal lattice Fe), a γ-phase (solid solution based on the FCC crystal lattice Fe), carbides of complex composition Me₂₃C₆ and Me₆C, iron carbides Fe₃C and chromium Cr₃C₂. It was established that tempering of the deposited layer does not lead to a change in the morphology of the structure formed by grains of eutectic and a solid solution based on α-iron (BCC crystal lattice). The main phases are α-Fe (85 wt. %) and carbides of complex composition Me₂₃C₆ (9 wt. %) and Me₆C (6 wt. %) forming eutectic grains. It has been established that the tempering of the deposited layer is accompanied by the pre-transformation of residual austenite with the formation of nanoscale particles of iron and chromium carbides along the boundaries of martensite crystals. Microcracks have been identified along the interfacial interfaces and in the volume of the plates of the carbide phase of eutectic grains, which can initiate the destruction of the deposited layer material during operation.

Welding technologies for layer composite are among the research priorities for the development of special structural materials with unique property combinations. A novel technology for producing permanent joints of metals and alloys with limited weldability is electron beam additive manufacturing. The development of new production processes requires the study of the effect of structural and phase heterogeneity in multilayer materials on their deformation behavior. An important scientific topic in this regard is the influence of the formed interface in the material on the process of plastic deformation. The kinetics of deformation fronts in an aluminum-magnesium alloy with structural inhomogeneity in the form of a weld seam obtained by friction stir welding is investigated. It is found that intermittent plastic flow is realized on the deformation curve in the samples in the initial state and after heat treatment. In addition, a yield plateau appears on the deformation curve in the annealed samples. During deformation of the annealed samples, the weld area divides the sample into sections of the base metal, where the Luders deformation occurs, and a stir zone, where localization of deformation in the yield plateau section does not occur. At the stage of intermittent plastic flow, the deformation process in both states occurs in a localized manner by nucleation and periodic propagation of deformation fronts over the entire working area of the sample. The kinetics of the fronts can be described within the framework of the autowave concept of plastic deformation similarly to homogeneous materials.

Natural wollastonite and diopside are unique fillers for the construction of efficient polymer composite materials with improved mechanical properties. Due to their high cost and scarcity in the domestic market, it is important to obtain these calcium-magnesium silicates (KMS) by solid-phase synthesis from inexpensive raw materials (agricultural high-tonnage rice production waste). The phase composition and properties of synthetic wollastonite and diopside were studied, and their effect on the performance properties of filled epoxy materials was evaluated. Studies have been conducted to determine the phase composition, porosity, and acid-base properties of synthesized fillers, and the effect of these characteristics on the performance properties of filled epoxy compositions has been evaluated. Synthetic wollastonite and diopside differ significantly in their phase composition. Synthetic wollastonite contains larnite as a side phase. Compared with diopside, it has a significantly larger specific pore surface and an order of magnitude larger total pore volume due to the lower temperature of its solid-phase synthesis and impurities of crystalline silicon dioxides. It was found that filling with silicates leads to the formation of a more organized polymer matrix structure. The obtained calcium-magnesium silicates are effective fillers of composite epoxy materials, the presence of which in the composition provides increased hardness, adhesive strength, wear resistance, reduces the coefficient of static friction, that is, improves the tribological properties of filled epoxy materials, which can be successfully used in mechanical engineering.

An urgent task of physical materials science is to improve the properties of metals and metal alloys necessary for operation. Despite significant progress in metal science and metallurgy, in particular in the creation of new alloys superior in their properties to alloys of the Al ‒ Si system, silumins will occupy a leading position in industry for a long time, which is associated with their manufacturability when used in almost all types of casting. Various methods of heat treatment are used to improve the structure and physico-mechanical properties of metal alloys. One of them is the technology of artificial aging, with the help of which it is possible to significantly change the physical and mechanical properties of metal alloys. The results of a comprehensive experimental study of the effect of a pulsed magnetic field on the aging process of AK9 aluminum alloy are presented. Information is provided on the chemical composition, modes of thermal and thermomagnetic treatments, and the main experimentally observed patterns of changes in microhardness and fine structure parameters of AK9 aluminum alloy aged for 4 hours at temperatures from 120 to 250 °C in a pulsed magnetic field with an amplitude of 557.2 kA/m and in its absence. It was found that the pulsed magnetic field significantly affects the strength properties and structure of the AK9 aluminum alloy, while it does not change the stages of the aging process. When a pulsed magnetic field is applied, the average size of coherent scattering blocks becomes larger, and the dislocation density and relative microdeformation are smaller than in its absence, which indicates the formation of a less pronounced crystal lattice. 

This study presents the synthesis of TiO₂ nanotubes using a combined hydrothermal–ultrasonic approach with short hydrothermal durations ranging from 4 to 10 hours, aiming to evaluate the controllability of morphology and crystalline structure for anticorrosion applications. Ultrasonic pretreatment was applied to enhance precursor dispersion and promote the formation of ordered nanotubular structures, thereby reducing synthesis time compared with conventional hydrothermal processes. The obtained materials were characterized using several complementary techniques: scanning electron microscopy (SEM) to analyze morphology and nanotube distribution, Raman spectroscopy and X-ray diffraction (XRD) to assess phase composition and crystallinity, and Fourier-transform infrared spectroscopy (FTIR) to identify surface bonding features. The results revealed apparent differences in nanotube organization, crystallinity, and phase development depending on the reaction duration, confirming that synthesis time plays a decisive role in tailoring structural parameters. These findings demonstrate that the hydrothermal–ultrasonic method provides an efficient and versatile route for fabricating TiO₂ nanotubes with tunable structural and functional properties. Furthermore, the synthesized nanostructures exhibit strong potential as carriers of corrosion inhibitors, enabling improved storage and controlled release within polymer-based protective coatings, thereby contributing to the development of next-generation anticorrosion technologies.

The results of studies of the chemical and granulometric composition of metal powder compositions of the EP648 brand (CrNi 50WoMoTiAlNb), fraction 40 ‒ 150 microns, obtained by gas atomization (MPC 1) and centrifugal plasma spraying (MPC 2), the particle size of the powders was determined by dry sieving according to GOST 18318 ‒ 94, the fluidity of the powders was checked in accordance with GOST 20899 ‒ 98. using a calibrated funnel (Hall device), the bulk density is in accordance with GOST 19440 ‒ 94. According to research, both batches of compositions comply with the regulatory documentation TU 78-265 ‒ 2023 in their parameters. Direct laser surfacing was carried out at a running energy of 60 J/mm and 70 J/mm on plates made of CrNi68WoMoTiAlCo-VD (EP693) grade material on an ILIST-XL technological laser growing unit using the studied metal-powder compositions, the surfacing modes were selected according to previous studies. In the samples deposited from composition 1, multiple pores (0.06 ‒ 0.08 mm) were found, as well as hot crystallization cracks 0.3 ‒ 0.6 mm long, extending along the boundary of columnar crystals. No defects were found in the samples deposited from composition 2. The main parameters of metal-powder compositions affecting the formation of structural defects in the deposited material are investigated. The main defects of the initial metal-powder compositions that have a negative hereditary effect on the quality of the deposited material have been identified: the presence of satellites (small particles connected to larger ones) and pores on the surface of the powder particles, which is directly related to the method of their preparation. The effect of linear energy on the residual porosity of the deposited material has been established.

Stainless steel powders occupy an important place in modern materials science as a promising raw material for the production of high-precision parts of complex geometry with minimal tolerances. The technology of metal powder casting using polymer binders Metal Injection Molding (MIM), which allows combining the advantages of powder metallurgy and plastic molding, has become the most widespread in industry. The method under consideration is particularly in demand in the manufacture of miniature components for responsible engineering purposes, where traditional processing methods are economically impractical or technologically limited. The key advantages of MIM technology when working with stainless steels are the ability to achieve a density of sintered products up to 95 ‒ 98 % of the theoretical, high repeatability of geometric parameters, as well as a significant reduction in mechanical post-processing. Of particular interest is the use of austenitic stainless steel grade 12X18H10T in MIM technology, as its products combine high corrosion resistance and heat resistance, and can also be used when working in aggressive conditions. The composition and technological parameters of granulate production for the MIM process using domestic materials are studied: 12X18H10T grade steel powders, polyformaldehyde binder and technological additives (stearic acid, beeswax and high-pressure polyethylene). The initial stainless steel powder has a regular spherical particle shape ranging in size from 5 to 25 microns. The use of scanning electron microscopy, determination of melt flow characteristics of thermoplastics, as well as the use of the pycnometric method made it possible to study the microstructure, rheological and physical properties of the obtained granules. It has been established that the samples from the developed granulate comply with the requirements of regulatory documents.

Increasing the energy-saving efficiency of converter processes involves the use of new designs of blast devices and methods of purging the converter bath. In this regard, it is extremely important to systematize previously obtained information and obtain new information on the features of the development of macrophysical phenomena in the zone of interaction of gas jets with the melt, the features of decarbonization and the conditions for the exit of exhaust gases to the surface of the bath. Using upgraded high-temperature modeling techniques for upper and combined purging conditions, comprehensive studies of the decarbonization process were performed to quantify carbon oxidation during the converter operation. The assessment of carbon oxidation in various reaction zones of the converter bath was carried out. It has been established that the place of predominant carbon oxidation is the reaction zone of interaction of oxygen jets with a bath. Improved mixing of the converter bath during bottom purging with neutral gas with a flow rate of 0.01 – 0.20 m3/t min is accompanied, compared with upper purging, by a decrease in transient carbon concentrations in the range from 0.9 – 1.2 to 0.4 – 0.5%, starting from which oxygen unused for the oxidation of impurities in the reaction zone begins to intensively flow deep into the melt. With a decrease in the carbon concentration in the melt below 1.0%, especially in the range of 0.5 – 0.1%, the supply of neutral gas through the bottom leads to an intensification of the decarbonization process in the melt volume.

Studies of the microstructure and mechanical characteristics of deposited coatings obtained using powder wires containing various alloying elements are presented. Special attention is paid to two types of hollow wires: EnDOtec DO*15, which consists of iron, chromium, molybdenum and tungsten, and the more complex Fe ‒ Si ‒ W ‒ Mn ‒ Cr ‒ C ‒ V system developed at the Siberian State Industrial University. The optimal structure of the samples was obtained, which made it possible to minimize the presence of non-metallic inclusions (silicates and oxides) that can negatively affect the mechanical characteristics of the materials. To assess the mechanical properties of the samples, measurements of nanohardness and modulus of elasticity were carried out using a NanoScan-4D nanohardometer. The structure of the EnDOtec DO*15 wire ensures a more uniform distribution of alloying elements, which in turn contributes to an increase in the strength of the material. The Fe ‒ Si ‒ W ‒ Mn ‒ Cr ‒ C ‒ V system has an increased number of nonmetallic inclusions, which negatively affects its mechanical properties. The best nanohardness values were recorded for EnDOtec wire, however, the Fe ‒ Si ‒ W ‒ Mn ‒ Cr ‒ C ‒ V system had an elasticity modulus of 125.84 GPa, which indicates its high efficiency under severe mechanical loads. The results obtained confirm the importance of choosing a powder wire depending on the specific requirements for durability and mechanical properties of the deposited coatings.

Currently, there are various, opposing points of view regarding the influence of non-metallic inclusions on the fatigue strength of steel. A number of studies by domestic and foreign metallurgists and materials scientists note the lack of correlation between the fatigue limit of steel and its total contamination with non-metallic inclusions. At the same time, numerous studies indicate that the presence of non-metallic inclusions has no practical effect on the cyclic fatigue strength of medium-strength steel. However, for steel with σв ≥ 1200 MPa, their negative effect is observed on transverse specimens, and for steel with σв ≥ 1700 MPa, also on longitudinal specimens. This article examines the conditions for fatigue crack initiation in steel under cyclic loads depending on its strength. It is shown that, under cyclic loading, the most dangerous stresses are tensile stresses, which form normal tensile stresses in the dislocation slip plane. A relationship has been obtained that allows one to determine the conditions under which the formation of crack nuclei from a surface defect or from non-metallic inclusions is most likely. It has been established that the influence of non-metallic inclusions on the possibility of fatigue crack formation is individual and depends on the morphology of non-metallic inclusions and their sizes. Large high-modulus non-metallic inclusions with a diameter of 5.0 – 7.0 μm or more can be responsible for the formation of cracks in the entire range of steel strength properties up to 500 to 2000 MPa. Ductile low-modulus aluminosilicate non-metallic inclusions with a Young's modulus no greater than that of the metallic matrix (200 – 210 GPa) do not cause the formation of cracks in the entire range of the ultimate tensile strength of steel. 

This paper presents a comprehensive overview of the current research directions in high-entropy alloys (HEAs), encompassing their fundamental aspects, processing routes, strengthening mechanisms, and application fields. The primary mechanisms governing the formation of the microstructure and phase composition in HEAs are analyzed, emphasizing the central role of high configurational entropy in stabilizing single-phase solid solutions and enabling the development of unique properties that surpass those of conventional alloys. The review systematically consolidates four primary research domains: the thermodynamic principles of phase formation, microstructural transformations, mechanical and functional properties, and the development of novel alloy classes and alloying strategies. Particular emphasis is placed on a comparative analysis of various HEA manufacturing methods, ranging from traditional melting and casting technologies—such as vacuum induction melting, vacuum arc remelting, and electroslag remelting—to powder metallurgy routes and modern innovative additive approaches, including selective laser melting, electron beam melting, and laser cladding. The study demonstrates how these diverse synthesis techniques enable control over microstructure, grain size, and phase distribution. The strengthening mechanisms of HEAs are examined, including solid-solution strengthening and precipitation hardening by nanoparticles, as well as the creation of heterogeneous structures and defect-mediated strengthening. These mechanisms are shown to be key to achieving an optimal balance of strength and ductility. The principal areas of practical HEA application are outlined, spanning the aerospace and energy industries to biomedical devices, protective coatings, and catalytic applications. The growing importance of HEAs for service under extreme conditions is highlighted, owing to their exceptional thermal stability and corrosion resistance. In conclusion, the review identifies promising avenues for future research, which include the development of scalable production methods, material standardization, and the implementation of computational models for the accelerated design of new compositions. 

The shadow economy as a multi-layered socio-economic phenomenon is an activity carried out outside of official control and statistical accounting, including cycles of production, distribution and consumption. The article offers a rethought approach to its analysis, with an emphasis on the impact on macroeconomic processes and the specifics of its manifestation in Uzbekistan. The relevance of the study is due to the systemic nature of the shadow sector, which reduces tax revenues, distorts statistics and slows down growth, but also indicates policy inefficiency. Based on the speeches of President Shavkat Mirziyoyev (2024 ‒ 2025) and statistical data, the severity of the problem in construction, services and industry is highlighted, where the share of shadow activity exceeds 40 %. The methodology combines regression analysis, indirect indicators and qualitative methods. The literature review covers foreign concepts and domestic approaches, classifying the shadow economy into "white collar", "gray" and "black". The results show that in 2024 The unobserved economy of Uzbekistan accounted for 34.8 % of GDP (505.65 trillion soums), with a predominance in agriculture (63.6 %) and construction (41.3 %). Corruption (CPI 2024: 32 points) is a key driver, exacerbated by fiscal pressures, regulatory density, and low trust. The discussion suggests a syncretic approach that combines disciplines to develop strategies: tax optimization, digitalization, and increased control. The conclusion highlights the need to integrate the informal sector for sustainable growth, with the prospect of institutional reforms.

Universities are increasingly facing difficulties in attracting applicants, which necessitates the development of effective strategies for managing the process of attracting future students. This paper presents and analyzes statistical data on the migration of school graduates using the example of the Kemerovo region – Kuzbass, demonstrating a steady trend of outflow of future applicants to large cities and metropolitan universities. Using the example of the Siberian State Industrial University (SibGIU), the existing system of attracting applicants is studied: its composition, structure and functions, as well as the points of interaction of departments responsible for career guidance, marketing, and the admission campaign. The key shortcomings in the organization of the SibGIU's applicant-forming system have been identified, including fragmented communications and insufficient coordination of activities. A model of interrelations and information flows between university structural units is presented, reflecting data exchange and communication processes between various functional units of an educational institution. This model allows for a deeper understanding of the complex mechanisms of integration and coordination of the activities of various departments, which is a key aspect of the effective functioning of a higher education institution in a dynamically changing educational environment. Based on the results obtained, the necessity of introducing a systematic approach to the management of the components of the recruitment of applicants is substantiated and the directions for improving the recruitment strategy are proposed: strengthening interdepartmental cooperation, developing regional marketing and optimizing career guidance practices to increase the competitiveness of the university. The authors proceed from the position that the management of the system of attracting applicants requires comprehensive management of all its components and relationships. Therefore, the departments involved in the recruitment of students and the nature of their interaction are considered as an object of systemic research and managerial influence.

A comparative analysis of the performance monitoring indicators of the Siberian State Industrial University (SibSIU) and technical universities of similar focus in the Siberian Federal District (Kuzbass and Novosibirsk State Technical Universities) was conducted in the main areas of activity. It was found that in the period from 2019 to 2023 (monitoring indicators for 2020 ‒ 2024), SibSIU had significantly worse indicators characterizing the research activities and staffing of the university. It was shown that despite the positive dynamics of the volume of income from research work per unit of teaching staff in SibSIU, the rate of increase of this indicator is significantly lower than that of the universities under consideration. It has been determined that the negative characteristic features of SibSIU are a significantly smaller (on average 2 times) teaching staff, reduced to the student body, and a significantly smaller (on average by 8 ‒ 9 %) share of the faculty in the total number of university personnel. The specified data, especially in connection with the low share of employees under 40 years old, indicate that the most significant problematic position of SibSIU is insufficient human resources. A comprehensive approach to the development of the human resources potential of the university in question is proposed for implementation with the development of an appropriate program, including the introduction of an individual bonus system for employees, a system of remuneration of the teaching staff based on an effective contract, improvement of the intra-university system of additional education for university employees, the formation and development of a strategic and operational personnel reserve for the positions of faculty.