When rolled and cooled on cooling beds, the long product acquires defects such as sickliness, longitudinal curvature and boxiness. To eliminate these defects, leveling in roller leveling machines with the method of elastic-plastic bending is used. In the course of material research, it was found that there are no works related to leveling asymmetric profiles. This paper is a starting point for the development of a leveling technology for asymmetric profiles, by the example of rail dressing. According to the other authors it is necessary to achieve a high rate of plastic deformation penetration in the straightening process. The article presents the results of 3D modelling of asymmetric profile leveling process by the example of rail liner profile in Deform 3D software package. Stress-strain state data were obtained and results were analysed. According to calculation results, distribution graph of plastic strain penetration coefficient has been plotted. It is noted that the maximum value of plastic strain penetration coefficient is observed for roll 3. The defects of the rolled products will be eliminated.

Thin-walled metal products of frame-cellular and ordered honeycomb structures are widely used as: parts of lightweight load-bearing, reinforcing, insulating, enclosing, shock-damping structures; structural elements capable of being in a liquid or gaseous medium, completely or partially passing through a flow of substance or energy, applicable for separating waste during the purification of gases and liquids; noise absorption parts, explosion and flame arresters, heat exchange, adsorption, acoustic devices, elements of current sources, catalysts, crystallizers, electrodes, as well as a reinforcing frame of composite materials from the metal-polymer group. However, the known methods of their production are characterized by high technological risks, as  well as complexity, labor intensity and other disadvantages. In this regard, the task was set todevelop and test a technology for the production of such cast iron products while minimizing such disadvantages of known technical solutions as high risks of violation of geometric accuracy and labor-intensive manufacturing, as well as insufficient assembly variability, leading to limited possibilities for controlling the operational properties and characteristics of the product taking into account its functional purpose. An innovative technology for the production of such products by lost foam casting is proposed. A special feature is the assembly of the lost pattern structure from repeating cells, and by forming from parallel located foam plates-layers with through passage holes, offset relative to each other. In this case, the number, thickness, type and magnitude of the relative displacement of the plate layers, the cross-sectional shape of the through holes and the angle of deviation of their symmetry axes from the normal to the surface of plates vary. The technology has undergone successful pilot testing and is recommended for implementation in existing production conditions.

An experimental testing of the technology for obtaining a deformed Co-28Cr-6Mo alloy using radial shear rolling is presented. Mechanical peeled and homogenized ingots of vacuum induction melting with a diameter of 57 mm were subjected to radial shear rolling in 4-5 passes to bars with a diameter of 18 and 29 mm at a temperature of 1200 °C with quenching of the final profile in water or cooling in air. A study of the microstructure, mechanical properties in the cast and deformed state was carried out. The requirements of GOST ISO 5832-12-2009 in terms of normalized indicators - tensile strength, yield strength and relative elongation are fully satisfied. At the same time, there is an increase in relative elongation by 1.4-1.6 times compared with the initial cast state and an excess of regulatory requirements by 3.0-3.3 times. The experimental technology has been implemented at NUST MISIS radial shear rolling mills and has the prospect of industrial scaling. The very significant advantages of the proposed technology include a small total elongation ratio (μ = 3.86), which ensures that the requirements of GOST on mechanical properties for the deformed Co-Cr-Mo alloy are met.The study was supported by the Russian Science Foundation grant No. 23-19-00477, https://rscf.ru/project/23-19-00477/.

Industrial water supply systems at many facilities use water from natural sources, and often it must be of high quality. One of the main consumers of water at present is metallurgical production. Most often, the water used by metallurgical enterprises is added to the circulating water supply system to replace water lost as a result of purging, evaporation, wind transfer, leaks, steam or intake from these systems. The make-up water directed to compensate for losses must undergo thorough preparation in order to avoid the formation of deposits, corrosion and other problems in the circulating water supply system. The scheme and technology of the water treatment process for metallurgical production depends on the parameters of the source water and the quality requirements of the prepared make-up water, ensuring the desired quality of the recycled water. The main requirement for the quality of make-up water is the low hardness content obtained during water treatment. One of the promising methods of water treatment in our time are membrane technologies. The steady reduction in production costs per 1 m3 of water by reverse osmosis allows it to be used as a method of reducing the hardness (softening) of water, instead of the widely used ion exchange. This article shows the fundamental possibility of using the reverse osmosis process for the preparation of make-up water, which allows to reduce the amount of used reagents significantly and to reduce capital and operating costs. The results of the calculation of three variants of reverse osmosis plant schemes are presented: with one stage for concentrate, with two stages for concentrate and with the return of part of the concentrate to the cycle. The presented schemes have energy consumption from 0.18 to 0.65 kWh/m3, salinity and residual hardness of no more than 31 mg/dm3 and 0.07 mg-eq/dm3. These schemes also differ in the volume and concentration of the discharged concentrate, which makes it possible to optimize the anthropogenic load on the environment, the possibility of reducing resource consumption is shown.The researches were carried out using D. Mendeleev Center for collective use of scientific equipment, within the framework of the project No. 075-15-2021-688.

Wastewater treatment of metalworking processes from oil products is a complex and urgent task. Strict requirements on the part of the water utility and organizations that control the discharge of industrial effluents into water bodies dictate the need to search for new and improve traditional methods for removing oil products from water. Physico-chemical purification and, in particular, coagulation is the fundamental process of water purification. Unfortunately, traditional reagents based on aluminum or iron salts have long been obsolete, and modern titanium-containing reagents are too expensive. Sample of a complex titanium-containing coagulant was studied in the processes of wastewater treatment of gear-cutting, hardening and rolling sections. Oil products were chosen as the key pollutant. It has been established that, in terms of their effectiveness, complex titanium-containing reagents are significantly superior to both the mixed coagulant based on aluminum and iron sulfates and the traditional and most common aluminum sulfate. Regardless of the type of waste water, the residual concentration of oil products in water when using a complex coagulant was at the solubility limit and amounted to ~1 mg/dm3. The use of complex titanium-containing reagents ensured the minimum residual content of suspended solids, and also made it possible to reduce the sedimentation time of coagulation sludge and their filtration time by 1.5–2.0 times compared with a mixture of salts and individual aluminum sulfate respectively. Based on the data obtained as a result of the experiments and a preliminary environmental and economic calculation, it was concluded that the use of complex titanium-containing coagulants in the processes of wastewater treatment of metallurgical enterprises from oil products and suspended solids was highly promising.The researches were carried out using D. Mendeleev Center for collective use of scientific equipment, within the framework of the project No. 075-15-2021-688.

Mathematical models of multivariate payback periods for a metallurgical investment project have been developed, allowing for a phased situational simulation of the accumulation of expected income directed to reinvestment. Currently, a variety of methods for evaluating the effectiveness of projects are used, the choice of which depends on the scale and duration of its implementation, on the volume of investments, on the type of financial stability of the enterprise. The proposed multivariate approach to evaluating the effectiveness of the project, considered on a specific example of the reconstruction of the electric steel-smelting shop. Three types of structured mathematical models for calculating the effectiveness of an investment project are given. Many models 1 as basic options assume that initially cash flows after the reconstruction of modernization will flow evenly over time intervals (years, quarters or months). Model 2 is planned taking into account the uneven receipt of components of cash income. So, at the first stages of time, it is planned to reduce net profit, and then increase it compared to the initial values. The total depreciation deductions from the introduction of capital investments by stages will decrease. Model 3 is a development of models 2, and is determined by complex (dynamic) methods, where the effectiveness of the investment project is evaluated taking into account the discounting of income. The algorithmic support of the decision support system on the timing of the effectiveness of a metallurgical investment project is presented. The generated models for calculating the effectiveness of the project are presented in the form of special tables that correspond to the step-by-step procedure for determining situational options provided to the customer of the project to select a rational option for the payback period when it is implemented in the electric steelmaking shop of EVRAZ ZSMK JSC.

Graphite products, including arc furnace electrodes, are characterized by mass loss during operation in high-temperature conditions. The consumption of electrodes depends on many factors: the pressure of the gas phase (in particular, the oxidizing agent), the average temperature over the electrode surface, and the quality of the product itself. The maximum oxidation rate is reached in the part closest to the metal, which is determined by the temperature gradient over the electrode surface from the area of the holders to the end of the electrode. At the same time, as the operation progresses, the electrode changes its shape from cylindrical to conical. Depending on the temperatures, three modes of oxidation can be distinguished, depending on the limiting factor. At the same time, the third mode is typical for arc furnaces – it is limited by mass transfer, which is caused by elevated temperatures over the electrode surface. This explains the low applicability of standard solutions used to improve the oxidative resistance of graphite products (including magnesium electrolysis anodes) operated under different temperature conditions and, accordingly, under a different oxidation regime – the formation of protective glassy coatings using borate or phosphate solutions. In order to improve the oxidation resistance of arc furnace electrodes, it is possible to adjust the technological modes of their manufacture or additional technical solutions in the field of operating electrodes directly in arc furnaces (for example, cooling by spraying water in the area of electrode holders). The mechanisms of siliconization of graphite, as well as the oxidation of the formed silicon carbide, are considered. It is proposed to use the carbothermal reduction of silicon oxide in order to obtain a protective coating on the surface of electrodes containing silicon carbide, as an alternative to expensive siliconizing processes. A variant of increasing the oxidative resistance of samples during the formation of a coating containing chromium carbide is also considered. The proposed solutions have the potential to be implemented on the basis of target enterprises, which is due to the possibility of reducing the rate of electrode oxidation by half – which can reduce the cost of metal production by approximately 8,5%.

Rolling contact fatigue is a common cause of rail failure due to repetitive stresses at the point of contact of the wheel with the rail. This phenomenon is a real problem that greatly affects the safety of train traffic. The tasks of preventive and corrective maintenance have a great impact on the life cycle cost of rail operation, and therefore advanced strategies based on forecasting functions are needed to reduce it. This requires a comprehensive assessment of defects of contact fatigue origin using modern research methods. In this paper, the microstructure of the metal surface layer and the mechanical properties of the metal of the rail head after various operating conditions are investigated. The analysis of the shape and size of defects of contact fatigue damage is carried out.

In this article, the features of magnetic abrasive finishing of contacting conical surfaces are considered. The main problems arising in the processing of critical operational surfaces of a conical geometric shape are described. The main task is to ensure the quality of the contacting conical surfaces of the ring and the synchronizer cone. As a solution to the problem, the application of the method of magnetic abrasive finishing is proposed. The main parameters of magnetic abrasive finishing and their influence on the effectiveness of the method are described. A method of magnetic abrasive finishing of conical and cylindrical surfaces is proposed, which is based on step-by-step processing taking into account the combination of various working movements. The simulation of the distribution of magnetic induction in the working gap during the processing of the conical surfaces of the ring and cone is carried out. Graphs of the distribution of magnetic induction along the treated surfaces are obtained. The results of the conducted studies allow us to evaluate the distribution of magnetic induction during the processing of conical surfaces in order to further consider the influence of the distribution of magnetic induction on the quality of the processed conical surfaces of mating products.

Since the mid 1930-s soviet metallurgists made lot efforts for creation the optimal tanks hull armor system. Due to irresistible technological difficulties, all plans about mass production of heterogeneous armor were rejected. Therefore, the new soviet tanks, designed in the pre-war period, received homogeneous armor of high (T-40 and T-34) or medium (KV) hardness. The armor system of the new heavy tank of the KV series was based on the 42S steel grade. It was distinguished by high manufacturability, acceptable mechanical properties. The relatively low content of scarce alloying elements made this steel inexpensive in fabrication, which made it possible to deploy mass production of armor for Soviet heavy tanks even under the most difficult conditions of evacuation to the Urals.The metallurgical part of the work was carried out within the framework of the Spin program.