A brief overview of the latest experimental results of the study of cement as a structural component of perlite, obtained by transmission microscopy methods for various types of deformation is presented. The behavior of lamellar and granular cementite under types of active deformation (forging, stamping, drawing, rolling, long-term operation of rails) has been studied. Studies of granular perlite on samples of carbon eutectoid steel grade U8 containing 0.8% C, 0.18 % Mn, 0.22% Si, 0.17% Cr, 0.12%Ni, 0.10 % Cu are presented. The historical aspect of the origin of the name cementite from the history of the metallographic study of cementite as an independent phase is considered. An example of the practical application of pearlitic steel in the construction of the Akashi-Kaike bridge in Japan (the longest single-span suspension bridge based on huge pearlitic steel cables) is given Attention is paid to the analysis of transformation during various technological processes, its morphology and structural features, and the main mechanisms of destruction are analyzed. It was revealed that with a large missed tonnage, a critical density of defects accumulates in the surface layer, which inhibits the development of reversible elastic deformation and the involvement (development) of the mechanism of plastic distortion. It is suggested that an increase in the service life of rails can be achieved due to a longer preservation of a structure capable of developing reversible deformation processes that exclude the destruction of cementite plates in pearlite colonies with subsequent movement of carbon atoms to defects (dislocations) and the iron lattice region

The work was performed using physical methods of materials science, destructive and non-destructive testing. Samples of structural carbon and low-alloy steels of grades St3sp, 10, 09G2S, 17GS have been studied. The analysis of changes in the structure of welded joints made of structural steels under the influence of plastic deformation is carried out. The material for artificial defects was graphite and crushed glass, which were introduced into the welding bath. The results of the study of samples with artificial defects and defect-free samples made by manual arc welding and modulated current welding are presented. Based on the mathematical patterns of changes in the parameters of acoustic emission (AE) of the signal for the studied steels of grades St3sp, 10, 09G2S, 17GS, a four-parameter three-level criterion for determining the stage of plastic deformation has been developed. The criterion under consideration allows us to qualitatively assess the degree of plastic deformation during stress tests of pipelines (throughout the AE location area), which is especially important for pipes with different wall thinning. In the fine structure of the zone of thermal influence of welding at the fusion line and in the deposited metal, bending extinction contours were revealed, indicating the presence of internal stresses. The number of contours increases as you approach the fusion line. The morphological components, regardless of the welding method, in the structure of the base metal are lamellar perlite and ferrite, in the structure of the seam metal – lamellar perlite, ferrite and martensite (the volume fraction depends on the welding method).

Modification of the grain structure of aluminum alloys in order to improve their physical and mechanical properties is an urgent task of modern materials science. One of the most promising methods of modification is the introduction of highly dispersed ceramic particles into the composition of alloys as modifiers of the second kind. However, in traditional conditions of foundry production it is rather difficult to realize their mechanical mixing, as the particles are prone to agglomeration, and also there is a concomitant saturation of the melt with undesirable gaseous products and impurities. In this connection, the method of self-propagating high-temperature synthesis (SHS), which makes it possible to obtain high-dispersity phases directly in the melt from micron-sized elemental powders. This makes it possible to bypass the purchase of expensive nanoscale precursors, as well as to reduce energy consumption and time to obtain the final product. The results of SHS of highly dispersed phase of titanium carbide (size 110 ‒ 300 nm) in the amount of 10 % (by mass) in the composition of widely used industrial aluminum alloys of different systems (AMg2, AMg6, AM4,5Kd, AK10M2N, D16 and B95) are presented. It is shown that the SHS method provides obtaining and uniformity of ceramic phase distribution over the matrix volume. Hardness evaluation proves that the presence of titanium carbide allows to achieve higher values in comparison with matrix alloys. The modifying effect of the presence of carbide phase particles has been evaluated, and the results show that matrix grain refinement by 2‒7 times is achieved. This leads, according to calculations and experimental data, to an increase in strength by 15‒40 MPa and hardness by 8‒42 NV. The method of SHS of ceramic phase of titanium carbide in the composition of industrial aluminum alloys is a promising method of modifying the grain structure of alloys.

Aluminum alloys have high corrosion resistance and weldability and are widely used in various manufacturing industries (aviation, automotive, shipbuilding). In this work, ER5356 welding wire with a diameter of 1.2 mm is used as a material for surfacing, and Al-5Mg alloys are manufactured by the method of wire-arc additive manufacturing based on cold metal transfer (WAAM-CMT) using three different welding arc modes (CMT, CMT-ADV, CMT-P). The study of the phase composition, microstructure and microhardness of Al-5Mg alloy samples was carried out. The results show that when using different arc modes, the diffraction patterns of α-Al differ significantly, and the main components of Al-5Mg alloys are α-Al and β-Al3Mg2. Two regions of microstructure are observed: the interlayer region (MSO) and the region of the inner layer (OAT), small columnar grains with pores and cracks are formed in the MSO, and large equiaxed grains are formed in the OAT. For all arc modes, the microhardness of the upper and lower regions of the sample is slightly greater than the average region. The microhardness of the sample produced according to the SMT-ADV mode (compared with the SMT and SMT-P modes) has the highest average value. This is mainly due to the fact that with a lower heat input, grains with the smallest size are formed (31.4–89.4 microns in MSO, 59.9–106.9 microns in OATS).

The increase in axial loads and the mass of rolling stock, typical for modern heavy haul traffic, as well as a significant increase in the speeds of passenger trains, increase the load on the railway track. At the same time, on the part of consumers of rail products, requirements are being put forward to increase the time of inter-repair work as well as the durability and reliability of rails as the main and most loaded element of the upper structure of the track. The operational stability of rails is largely determined by the structural and phase state of steel. It is important to establish the regularities of the formation of the microstructure of rails, which depends on the chemical composition of steel and the influence of the structure on the properties of finished products. As a result of the conducted studies, the links between the structure parameters, the physical and mechanical properties of rails, the content of the main chemical elements in steel, and the interplate distance of perlite have been established. The authors proposed to obtain a finely dispersed perlite structure that provides the highest operational properties

It is shown that titanium-coated powder wires are widely used for surfacing steels with high wear resistance. It is determined that in the calculations it is necessary to take into account the thermodynamic factor, which makes it possible to assess the chemical affinity between the substances that make up the welding (surfacing) materials and the most likely ways of chemical transformations, taking into account all possible reactions and states of the reagents. It is indicated that it is necessary to consider the possibility of forming a number of oxide non-metallic inclusions that are not characteristic for temperatures of electric steelmaking processes. A comparative assessment of the thermodynamic properties (∆_rH°(T), ∆_rG°(T)) of reactions with titanium in the metal oxide – titanium system under standard conditions is given. The thermodynamic properties of [∆_rH°(T), ∆_rG°(T)] reduction reactions of FeO, Fe₃O₄, Fe₂O₃, MnO, SiO₂, Cr₂O₃, Al₂O₃, CaO, MgO oxides with titanium (45 reactions) in metal oxide – titanium systems under standard conditions with the formation of TiO oxides were evaluated, Ti₂O₃, Ti₃O₅, Ti₄O₇, TiO₂. It is shown that the reactions of titanium with calcium and iron oxides are most likely to occur and, accordingly, the greatest heat release, while the least probability of occurrence and, accordingly, heat release is observed during the reduction of silicon and aluminum oxide. Reactions with manganese and chromium oxides occupy an intermediate place. The reduction reaction of magnesium oxide with titanium is not possible without an additional source of heat. The calculation of the thermodynamic properties of the reactions showed that the use of titanium as a solvent for electric arc welding with a powder wire is quite acceptable.

The microstructure and tensile mechanical properties of samples made of a heat-resistant nickel-based alloy obtained using the direct energy and material supply (LP-DED) process have been studied. The power of the laser radiation varied from 1200 to 2000 watts. It was noted that low laser power can lead to higher cooling rates and defects in the microstructure of the samples. The radiation power of 2000 W resulted in the highest mechanical properties under tension. The effect of heat treatment on microstructure, hardness and tensile properties was investigated. When examining the samples after destruction, it was found that defects in the form of non‒melts and cracks are present in the fractures of the samples obtained at a power of 1400 - 1800 watts. In the fractures of the samples made at a laser power of 1200 and 1600 W, there are non-molten powder particles. On the fracture surfaces of all samples, pits and the classic shape of a cup and cone were present, indicating a viscous fracture mechanism. It was found that heat treatment can completely homogenize the microstructure, lead to relatively homogeneous, equiaxed grains and increase the hardness of the material. Heat treatment reduces the anisotropy of properties, leads to an increase in the level of tensile properties at different laser power. The study provides an initial basis to help designers and specialists with the choice of laser power, as well as to understand its effect on a heat-resistant alloy, its effect on microstructure and mechanical properties at room temperature.

A simple and inexpensive method for the synthesis of porous skeletons of MAX phases Ti₃SiC₂ and Ti₃AlC₂ by the SHS method in air and in river sand filling, in which the use of a closed reactor with a special atmosphere or vacuum is not required, is considered. The study of the macrostructure of synthesized samples based on the MAX phases of titanium aluminum carbide and titanium silicon carbide showed that the samples have the same porosity of about 50 – 60 %, the open porosity is about 40 %. The average pore size ranges from 10 to 350 microns. The microstructure of the porous Ti₃SiC₂ and Ti₃AlC₂ frameworks consists of characteristic multidirectional blocks of MAX-phase plates, as well as a small number of equiaxed TiC particles surrounded by a single TiSi or TiAl phase, respectively. It is shown that the synthesis of porous frameworks in air leads to the formation of oxide and nitride phases that tightly cover surfaces up to 100 microns thick. The SHS process under a layer of sand makes it possible to reduce the average thickness of oxide and nitride films on the surface of the SHS frame to 20 microns. A subsurface layer consisting of two phases was found on the synthesized samples: TiC – TiSi in the Ti₃SiC₂ frame and TiC – TiAl in the Ti₃AlC₂ frame, the thickness of which is reduced from 50 microns (SHS in air) to 30 microns (SHS under a layer of sand). It was found that oxide and nitride films were absent in closed pores due to the fact that atmospheric gases did not have access to them when the samples cooled

The main stage of surface preparation for hot-dip galvanizing is the fluxing operation. Immersing products in flux removes oxide films and activates the surface, providing a bond between the base metal and the zinc coating. The purpose of this work is to compare five modifications of the most popular flux composition based on ZnCl₂ and NH₄C1 produced by Promkhimperm with an imported sample produced in Spain, as well as to identify the influence of the modifying components of the compositions on the quality of galvanized products. The samples were immersed in a flux solution heated to 50 °C, kept in the solution for 15 minutes, and then dried. The study of the structure and elemental analysis of flux samples dried on a steel surface was studied on a TESCAN VEGA SB scanning electron microscope, with the uniformity of element distribution assessed by mapping carried out by energy-dispersive microanalysis using the INCA-act attachment. To determine the wetting ability of fluxes, contact angle measurements were carried out using the “seated drop” method. The wetting and spreading of zinc melt over fluxed steel was assessed by the cleanliness of the holes (zinc plating) on the samples. It has been established that all presented fluxes have good surface wetting properties. Most fluxes have a frosty crystallization pattern of zinc chloride. All modifying components of fluxes, with the exception of manganese, are distributed evenly over the surface. A visual assessment of the quality of the zinc coating formed after fluxing with various compositions showed that the best galvanization of holes with a diameter of 10 mm is provided after fluxes with the ratio of the main components: 21 % ZnCl₂ – 20 % NH₄Cl. A flux with more complete sorption of impurities made it possible to obtain a clean hanging hole with a diameter of 4 mm

The microstructure and mechanical properties of a matrix composite based on aluminum alloy AA2024 reinforced with TiO₂ nanoparticles have been studied. AlMgCu intermetallic compound is formed in an aluminum matrix reinforced with TiO₂ nanoparticles with various concentrations (0, 2.5, 5.0 and 7.5 %) obtained using mixing casting technology. The mixing casting process was followed by subsequent heat treatment at 500 °C. The alloy was then rapidly cooled in water to a temperature of 25 °C and aged at 185 °C for 3 hours. This treatment leads to the dissolution of titanium nanoparticles in the matrix, and ultrafine compounds are formed around the grains of the aluminum composite. According to the results obtained, the compounds Al₇Cu₂Fe and Al(Cu, Mn, Fe, Si) form a single structure in the interendritic regions. When adding up to 2.5 % titanium oxide, the number of fine needle–like Al – Cu – Mg secretions near the dendritic regions increased, but further addition of titanium oxide reduced their number in this zone. After heat treatment with the addition of up to 7.5 % titanium oxide, needle–like Al – Cu – Mg secretions in the dendritic regions disappeared and fell out in the inner zone of the dendrites. When TiO₂ was added and heat treatment was carried out, the unreacted intermetallides and Al₃Ti were completely converted into Al₃MgCu. With an increase in the TiO₂ content from 5.0 to 7.5 %, instead of Al₂CuMg secretions, Al₆Mg₄Cu secretions were formed in the aluminum matrix. The addition of 5 % titanium oxide increases the hardness of the composite by about 33 % compared to samples without titanium oxide nanoparticles

Technological and mineralogical studies of samples of burnt limestone and pre-treated concentrate were performed. The processes of changing the mineral composition and moisture content of the MMC concentrate during its prophylaxis with burnt limestone have been studied. The mechanism and kinetics of water binding of wet iron ore concentrate in the process of mineral hydration are described. It is shown that almost all the minerals of burnt limestone participate to a certain extent in the process of concentrate prophylaxis. It has been experimentally established that the prophylaxis process takes place during the day, but the process is most intense in the first 4 hours after mixing the wet concentrate with burnt limestone.

National projects have been developed since 2000. At the first stage of the development of the country's strategy, federal targeted programs were developed, which began to be implemented in 2002. The second stage of the development of the country's strategy is the implementation of national projects in 2005, which began after a special commission under the President of the Russian Federation was established. The following projects were implemented: "Education", "Health", "Affordable and comfortable housing for Russian citizens", "Development of the agro-industrial complex". All these areas had their own goals, objectives and implementation plans. Monetary funds were allocated from the federal budget. The concept of a national project is presented, a brief overview of national projects from different countries is made, which national projects are being implemented in the Kaliningrad region and what impact they have on the development of the region. On the basis of the data published by the Government of the Kaliningrad region and statistical data, the main directions of development of national projects were studied. It was revealed that the residents of the region take an active part in the development of projects within the framework of creating a comfortable environment, participate in the All-Russian competition for the best projects, which allows to improve the territories of the entire region. A chronological analysis of the structure regarding the sources of financing of national projects was carried out, the sources of the budget for financing projects were determined. The conducted research has shown that national projects are financed to a greater extent from the federal budget and partially from the regional one. Of course, such projects affect the economic development of the region. The Kaliningrad region is one of the attractive regions for tourists, due to which revenues to the regional budget increase. This makes it possible to finance regional projects.

The features and role of digitalization in the development of special economic zones (SEZ) are described. Digitalization is a general term for the digital transformation of society and the economy. The use of digitalization technologies makes it possible to automate production processes and reduce costs, as well as improve product quality. The Kaliningrad region is considered as an example. Today, digital technologies are successfully used in various industries in the Kaliningrad region. This helps to attract investments to the region and create new jobs for the population. The existing features of the digital transformation of the region are highlighted. Digitalization tools that have an impact on improving the efficiency of pricing in special economic zones are considered, since pricing in these zones is crucial for attracting investors and creating a competitive environment. Digital communication channels, logistical features in the SEZ and digital platforms that affect the effectiveness of pricing in the region are analyzed. It is noted that the advantage of the development of pricing in the context of digitalization is the creation of conditions for the development of e-commerce and online commerce, which opens up new opportunities for entrepreneurs and consumers, improving the accessibility and convenience of purchases. A number of important factors have been identified to increase the efficiency and development of pricing in the SEZ (improvement of analytics, optimization of warehousing and logistics, increased communication with customers, effective dissemination of information). Thanks to digitalization tools, it becomes possible to reduce prices for goods or services, make prices more transparent to consumers, and also develop e-commerce in the region, increasing supplies to local markets through the ports of the Kaliningrad region

In conditions of rapid scientific and technological progress, the role of transport (and related transport safety, infrastructure, problematic factors, etc.) is extremely significant. At the same time, many large cities (including Russian cities) are characterized by the high rates of construction and development of suburbs and new neighborhoods without the corresponding facilities (or at a much slower pace) of transport routes, access roads, stops, subway stations, appropriate infrastructure, etc. One of the most pronounced examples is the town of Murino (a suburb of St. Petersburg), whose population has grown over the last 9 years from 9.9 thousand people (2014) to 104 thousand people (2023), with an average annual increase of 10 thousand by 2030. Existing transportation problems cause suburban residents travel 2-3 km to the nearest metro station for 50 minutes. Authors proposed a new solution, tested it, and confirmed its reliability and efficiency: transport-infrastructure complexes developed by Unitsky String Technologies (uST) as a kind of rail off-street transport. In particular, based on available analytical and calculation data, the study proposes the construction of a commercial project on the route from Murino to Devyatkino metro station with a length of 3.4 km and 6 stations. The article also presents a number of advantages of uST, substantiates the economic efficiency of the project (based on payback period estimation), provides financial and organizational scenarios of its implementation, and provides further prospects.