Iron-carbon Alloys Research Articles

Surface matters: Decarburising wootz crucible steel ingots

Wootz, the Indian crucible steel, is a hypereutectoid iron–carbon alloy and famous for its outstanding qualities. Due to the paucity of archaeological and historical ingot finds and conservative sampling strategies, discussions of the homogeneity of such ingots and the microstructural representativeness of samples have remained generic and assumptive. Thus two major shortcomings in the study of crucible steel ingots include the determination of their absolute carbon content and its relative distribution across the ingots. The recent discovery of a large hoard of wootz ingots from Telangana (Jaikishan et al. 2021) offered a unique opportunity to study their microstructure and determine their carbon content.Reports based on traditional metallography suggest a wide carbon range, from 1 to 2 wt% carbon, for similar ingots (Scott 2013). Recent work based on image analysis (Desai and Rehren 2023) offered narrower carbon estimates (about 1.8 wt%) for several of the recently discovered ingots, with some variation in concentration towards the edge of the samples. As a collaborative effort to determine absolute carbon values and potential uneven distribution of the carbon in the Telangana ingots, traditional metallography was coupled with laser-induced breakdown spectroscopy (LIBS). Beyond documenting the microstructure across several ingots, the study provides macrostructural evidence of rim decarburisation, which we believe to be intentional. This study presents the micro- and macrostructure of two of the hypereutectoid Telangana ingots, highlighting the skill of the craftsmen in decarburising the outer surfaces of their ingots, potentially for ease of subsequent forging.

Метод поєднання ливарного та термічного процесів виготовлення виливків із залізовуглецевих сплавів

With the help of innovations at an industrial enterprise, it is possible to increase labor efficiency and reduce the resource intensity of production. The relevance of the development of the technology of metal casting in sand molds, as the most common casting process, is justified by the fact that up to 80 % of the tonnage of castings is produced in such molds, including special types of casting in molds from sand materials. 60-70 % of the equipment capacities, areas, and personnel of foundry shops are attributed to molding processes, including mixing and rod production. Pollution "due to the mold" can reach up to 80%. A significant potential for the development of foundry mold technology is the improvement of the processes of casting metal into molds made of loose sand without a binding component, in particular, according to the Lost Foam Casting Process (LFC). The authors present the concept of improving the processes of casting metal into molds made of loose sand by the method of dual application of molding materials and give examples of such application. The use of loose molding sand for rapid cooling of the casting, including heat treatment, is able to strengthen its metal and reduce the duration of cooling of the casting in the mold, which leads to an increase in the productivity of foundries without increasing the number of furnace equipment and loose mold filler. The applied method of isothermal hardening (austempering) from the hot state of castings from iron-carbon alloys excludes heating with exposure for austenization of castings, which reduces the cost, time and energy consumption of obtaining products with a strengthened bainite structure, which, in fact, corresponds to the concept of realizing internal reserves as a foundry sand mold, and cast metal. Some foundry enterprises of the Vinnytsia region also use LFC or have concluded contracts, planning to reconstruct their shops for this ecological and economically beneficial foundry technology.

Fine Structure of Lamellar Pearlite in Iron–Carbon Alloys (Review)

Fine Structure of Lamellar Pearlite in Iron–Carbon Alloys (Review)

Study on mechanism of micro-cutting iron-carbon alloys of silicon carbide particles based on molecular dynamics

Study on mechanism of micro-cutting iron-carbon alloys of silicon carbide particles based on molecular dynamics

Темір-көміртекті қорытпалардағы негізгі элементтермен және металл емес қосындылармен сирек жер металдарының әрекеттесуін зерттеу

The proposed article is devoted to the study of the interaction of rare earth metals with basic elements and non-metallic compounds in iron-carbon alloys. The article discusses the method of modifying iron-carbon alloys with rare-earth metals, the nature and mechanisms of interaction of alloy components. The influence of rare earth metals and non-metallic mixtures on the properties of the material is analyzed. The qualitative composition of nonmetallic inclusions formed in steel grades 09G2FB and 17G1SU modified with yttrium and without the introduction of yttrium-containing material (SIITMISH-1) was studied by the X-ray spectral method. With the formation of complex compounds by the introduction of rare earth metal, as a result of which the alloy is purified from non-metallic compounds. Research in this area makes it possible to develop new materials with improved characteristics and optimize the processes of their production and processing

Ізотермічне гартування залізовуглецевих сплавів, суміщене з їх виливанням

Isothermal hardening (Austempering) of iron-based alloys with medium and high carbon content, which creates a metallic structure called bainite, is used to increase the strength and impact toughness of the metal. The parts are heated to a temperature approximately 200-300 °C below the solidification temperature of the metal, then cooled (hardened) fairly quickly to the temperature of the beginning of the bainite transformation, avoiding the martensitic transformation, and kept for a time sufficient to obtain the given bainite microstructure. IG is particularly advantageous for castings from high-strength cast iron (HC), adding to the high foundry performance of the growth of the mechanical characteristics of this alloy to the level of steel strength at a lower cost, density and energy consumption of HC casting compared to steel. The article examines methods of heat treatment of castings removed in a hot austenitic state from a sand mold, as a type of heat treatment of iron-carbon alloys combined with their casting. For this, casting according to gasification models was used, in which, due to the high fluidity of the dry sand of the casting mold, it is not difficult to remove hot castings from the mold for tempering. A number of IG methods previously patented by the FTIMS Institute of the National Academy of Sciences of the Russian Academy of Sciences have been supplemented by a new method of such hardening in a dosed amount of water, taking into account the effect of its film boiling. The new method includes the calculation of the optimal mass of quenching liquid - water with the aim of heating this mass of water to its boiling point at the time of cooling of the casting to the given temperature of the bainite transformation of the metal. The method saves the quenching liquid, simplifies the control of the duration of cooling, during which it allows the transportation of castings between the foundry and heat-treatment sections, which, in general, saves time, energy resources and the area of the workshop for obtaining heat-treated castings. Keywords: isothermal hardening, heat treatment, castings, austenite, lost foam casting.

ОБЗОР СОВРЕМЕННЫХ ДЕМПФИРУЮЩИХ СПЛАВОВ В КОНТЕКСТЕ ПЕРСПЕКТИВ АГРОПРОМЫШЛЕННОГО ПРИМЕНЕНИЯ

The article provides an information and analytical review of progressive scientific and technical solutions in the field of industrial use of modern damping alloys from the point of view of increasing the effectiveness of vibration control and industrial noise in the operation of machinery and equipment of the agro-industrial complex. In accordance with the generalized classification system for high-damping alloys, a comprehensive characteristic of alloys with an improved ability to dissipate (absorb) the energy of vibrations that occur in dynamically loaded parts (nodes) of agricultural machinery is presented. The main groups of damping alloys for effective vibration protection of elements of agroengineering systems have been identified by systematizing scientific and practical information about the key features of the most common alloys in science and industry with increased damping (dissipative) properties. It has been established that such iron-carbon alloys as alloyed steels and gray cast irons are among the most promising vibration- and noise-absorbing metal materials for the manufacture of agrotechnical facilities operating in the mode of cyclic and shock effects. The indicated iron-carbon alloys have demonstrated an increased ability to dissipate the energy of sound vibrations over a wide temperature range with an acceptable set of physico-mechanical, technological and operational parameters. It was found out that the mass use of non-ferrous metal alloys in the agro-industrial complex as vibration- and noise-absorbing metal materials is hindered by their high cost, as well as a rather limited combination of physico-mechanical (functional) properties, especially in the range of elevated temperatures. For this reason, it is recommended to pay attention to the study, development and modernization of special multicomponent damping coatings that can be applied to the main material of agrotechnical facilities using various technologies.

Control of Properties of Iron-Carbon Alloys Produced by Aluminothermy by Varying Technological Factors

Control of Properties of Iron-Carbon Alloys Produced by Aluminothermy by Varying Technological Factors

Structural transformations and their impact on the mechanical and antifriction properties in the process of alloying graphitized hypereutectoid steel with copper

The purpose of the work is to develop a cast antifriction material based on an iron-carbon alloy with a high copper content for use in large, heavy duty sliding friction units. Using the casting method in self-hardening liquid glass mixtures, two specimens of hypereutectoid graphitized steel with different copper contents (0.09 and 8.76 wt.%) were produced. To obtain graphite in the steel structure, modification with the silicocalcium (SiCa) was used. The microstructural examination was carried out using optical metallography, SEM and TEM methods. The impact of copper on the structure as well as the mechanical and antifriction properties of graphitized hypereutectoid steel was studied. It was found that adding 8.76 wt.% of copper to the steel composition leads to an increase in the Brinell hardness level of the material from 250 to 300 HB, ultimate tensile strength from 250 to 380 MPa and compressive strength from 1050 to 1200 MPa, which is associated with an increase in the microhardness of pearlite from 350 to 420 HV. To assess the impact of copper on the sliding friction coefficient of graphitized hypereutectoid steel, a curve of sliding friction coefficient vs applied load was plotted; the experiment was carried out according to the liner-on-disk scheme. The wear resistance of materials under sliding friction conditions was also assessed using this method. Copper alloying has a positive effect on the wear resistance of graphitized hypereutectoid steel by increasing the mechanical properties of the material and also by reducing the level of the sliding friction coefficient under boundary lubrication conditions.

Estimating carbon content in crucible steel using image analysis

Pre-industrial crucible steel ingots, produced in both Central and South Asia, are an important class of iron-carbon alloys. Their microstructure reflects their formation from a liquid alloy at a carbon content of 1.0–2.5wt%, which is higher than most mild steels but lower than most cast irons. This article introduces a tool to quantify the carbon content of such alloys based on an operator-supervised image analysis which determines the relative proportions of austenite/pearlite and cementite, respectively, from high-contrast back-scatter electron images of unetched samples. Using examples from a recently discovered hoard of crucible steel ingots in Telangana, south-central India, we demonstrate the capabilities of the tool and test its usefulness. The main benefit is in improving accuracy and precision in metallography-based carbon content determination in such alloys by reducing the uncertainty in area estimation in complex microstructures based on visual impression alone.

Research of the production of iron ore sinter from bauxite processing waste

This article presents the results of a study of the agglomeration of waste alumina ferrous sands and the use of sinter as a substitute for metal charge in steelmaking. At this time, in the process of processing bauxite, JSC "Aluminium of Kazakhstan" produces a large number of fines, which is of great interest to ferrous metallurgy. Wastes from alumina production include a variety of waste sludge, including red, gray sludge, and ferrous sands. According to the chemical composition, ferrous sands can be attributed to iron ore material with a high content of alumina. Most of these problems are eliminated by preliminary agglomeration of fines. In this work, agglomeration studies made it possible to establish the optimal parameters for sintering ferrous sands. When using 10% fuel, the best sintering performance is achieved. The optimal parameters for sintering ferrous sands mixed with other metallurgical wastes are such as productivity - 0.92 t / m2 h, mechanical strength - 80.0%, sintering speed - 19.3 mm/min, yield - 82.0%, the maximum temperature in the layer is 1340 °С. The results of laboratory melt carried out in an induction melting furnace indicate the possibility of using a sinter as a substitute for metal charge in iron and steel smelting. The conducted melting confirms the fundamental possibility of using a sinter, made from waste products of alumina production of ferrous sands, is a man-made charge material that is suitable for use as a 5% additive to the metal charge in the smelting of iron-carbon alloys similar in composition to cast irons.

Research of Increase of the Wear Resistance of Machine Parts and Tools by Surface Alloying

The work scientifically substantiates the application of an effective technology for increasing the wear resistance of machine parts and tools due to complex diffusion saturation of the surface layer of parts made of iron-carbon alloys in the process of casting on gasified models based on the optimization of the composition of saturating mixtures and the establishment of patterns of structure formation.
 The possibility of strengthening the surface of castings from cast iron SCH20 and steels of various composition (25L, 30L, 35L, 45L, 25HL, 110H13L), obtained by methods of casting in an open mold and on gasified models, has been established. It is shown that the diffusion boride layer on 35L steel, obtained during casting, has an order of magnitude greater thickness (up to 5 mm) compared to the diffusion layers obtained by chemical-thermal treatment methods (up to 0.25 mm). Analytical dependencies have been established that connect the components of the composition of the mixture (chromium boride (CrB2), boron carbide (B4C), graphite, bentonite, sodium fluoride (NaF)), which saturates, with wear resistance and the thickness of the diffusion layer after hardening in the process of obtaining a casting by the method of casting on gasified models.
 A new composition of the saturating medium has been developed for surface strengthening in the production of cast parts from gray iron, carbon and alloy steels by simultaneous saturation with boron and chromium, containing chromium boride, boron carbide, graphite, bentonite, sodium fluoride (50-60 wt. % B4C + 20-25 wt. % CrB2 + 2-3 wt. % + 5-15 wt. % finely dispersed graphite + 5-7 wt. % bentonite). The application of the developed strengthening technology allows to improve operational properties, in particular, the wear resistance of machine parts and tools up to 25 times (compared to previously used methods), as well as to reduce the labor intensity of the strengthening process by up to 3.5 times.
 Tests of dies for pressing wood waste into briquettes made of 45L steel, strengthened with the help of the developed technology, showed that their stability increases more than 4.5 times compared to the previously used ones made of HVH steel strengthened by carbonitriding, and the use of the developed strengthening technology allows reduce the cost of manufacturing this part by 1.5 times.

APPLICATION OF VACUUM SUCTION CASTING OF IRON-CARBON ALLOYS FOR THE PRODUCTION OF ENGINE PARTS

The use of vacuum suction casting technology for iron-carbon alloys for the production of internal combustion engine parts will improve their quality and wear resistance, preserve metal, and reduce emissions. The technology is widely used for non-ferrous alloys. At the same time, its implementation for iron-carbon alloys (including cast iron) in modern engine construction requires careful scientific and practical preparation. Problematic tasks arise when improving the pneumatic system of vacuum suction (large volumes of gas release), the stability of the metal pipeline (thermal overload in a high-temperature cast iron melt), and the stabilization of the casting microstructure (high-speed crystallization). The authors suggest using a specialized titanium alloy VT3-1 for the metal pipeline, for which the article calculates thermal loads during cyclic operation in the “Deep – take-out” mode for the use of cast irons of the SCH25 and VCH50-1.5 grades. For reliable operation of the metal pipeline and the absence of solidification of the melt on its inner surface, a thermal calculation method was develop, which allows determining the time of heat removal of overheating of the melt according to the diameter of the metal pipeline. The pneumatic system of the vacuum unit is supplement with a patented gas jet ejector, which, in combination with a powerful shop compressed air system, provides a full gas outlet. Applying the developed law of change in the discharge between atmospheric pressure and pressure in the mold cavity, the authors of the article regulate the rate of crystallization of castings, which makes it possible to form much smaller phases of perlite in the microstructure and reduce the presence of Ferrite. At the Enterprise "Pervomaiskdizelmash" using vacuum casting technology, blanks of guide bushings of engine valves 6CHN25/34 made of cast iron SCH25 and VCH50-1,5, as well as oils of piston rings made of cast iron VCH50-1,5 were obtained. The obtained parts showed an increased service life by 15-30%. Vacuum casting technology is recommend for iron-carbon alloys in the production of engine parts.

Are crucible steel ingots isotopically homogenous? AMS radiocarbon measurements on ingots from Telangana, India

Radiocarbon analysis is increasingly used to directly date archaeological and historical metal objects, ranging from low-carbon bloomery iron to steel and cast iron. However, little is known about the isotopic homogeneity of iron-carbon alloys, particularly relating to the formation of primary cementite during crystallisation. Here, we present 14C measurements for five crucible steel ingots and one crucible steel object from Telangana in south-central India. Two of the ingots were analysed twice. The results show a very wide scatter of 14C dates, far exceeding the expected age range for this assemblage. The repeat analysis of one of the ingots gave also widely different results, indicating a fundamental problem with the 14C analysis of crucible steel. We discuss the various factors that could have influenced the measured isotopic values, including variability in raw material, sampling contamination, and fractionation during the cleaning of the metal in hot acid leading to excessive sample mass losses prior to the extraction of carbon from the metal. We argue that mass-dependant fractionation of the different carbon isotopes between austenite and cementite during solidification of the ingot, and subsequent selective dissolution of one metal phase over the other, led to a distortion of the 14C signature to seemingly older ages. We recommend further research to explore the compound-specific isotopic signature of high-carbon iron alloys and the effect of selective corrosion on such material, to reduce potential errors in 14C dating of steel and cast iron.

REGULATION OF THE PROPERTIES OF SAND-CLAY MOLDING MIXTURES BY SODIUM PHOSPHATE ADDITIONS

Purpose. Study of the effect of sodium phosphate additives on the properties of a reversible sand-clay mixture in the green and dry state to improve the quality of castings from iron-carbon and aluminum alloys.
 Research methods. A reversible molding mixture based on quartz sand and kaolin clay was used. The effect of three additives (sodium tripolyphosphate, sodium hexametaphosphate, sodium pyrophosphate) in amounts from 0.5 to 2.0% was studied. Properties of mixture were determined using standard methods: clay component content, strength, gas permeability, crumbleness, flowability, formability, packing.
 Results. Effective additives have been studied to ensure the possibility of multiple use of reversible molding sand-clay mixtures. Special attention is paid to the regulation of the properties of the mixture in the dry state, since this issue has been much less researched today. For this purpose, sodium phosphates, which are produced by the chemical industry in sufficient quantities, were used for the first time. As materials that affect the properties of the mixture as a whole, they have not been considered before.
 Scientific novelty. For the first time, the positive effect of sodium phosphate additives on the physical and mechanical properties such as strength and crumbleness of reversible sand-clay mixtures was established. This effect is manifested in the fact that additives contribute to a slight improvement of properties of the green mixture and a very significant improvement of these properties of the dry mixture. There is practically no effect on important technological properties (flowability, formability, packing).
 Practical value. Based on the results of the experiments, it is recommended to use sodium tripolyphosphate or hexametaphosphate additives in the amount of 0.5 to 1.0 % to significantly improve the properties of dry sand-clay foundry molds. The use of these additives eliminates the appearance of surface defects in cast parts from aluminum and iron-carbon alloys.

РАЗРАБОТКИ ПОДПРОГРАММЫ «МЕТАЛЛУРГИЯ», ВЫПОЛНЕННЫЕ В ИНТЕРЕСАХ ПРОМЫШЛЕННЫХ ПРЕДПРИЯТИЙ

The main results of the implementation of the tasks of the subprogram “Metallurgy” of the State Research Program “Mechanics, Metallurgy, Diagnostics in Mechanical Engineering”, 2021–2025, with an applied orientation are presented, which are obtained by the organizations of the National Academy of Sciences of Belarus, the Ministry of Education and the Ministry of Industry of the Republic of Belarus. Their contribution to the solution of practical problems is shown. In the field of metallurgy of iron-carbon alloys, a range of new grades of steels for large gears and large castings of supporting systems of machines are developed. Distinctive features of the developed steels are the possibility to obtain higher hardness values of the hardened layer and teeth of cemented gears compared with counterparts from serial steels. A new sparingly alloyed steel for gearboxes of tractors BELARUS has been developed. The steel is characterized by high hardenability of cemented layer. In the field of metallurgy of non-ferrous metals and alloys, theoretical and technological bases for production of complex configuration castings are developed. Application of these castings improves the dimensional accuracy of products. In the field of hardening of steels and alloys, the technology of coating formation on the working surfaces of metallurgical and foundry equipment parts by mechanical cladding with flexible tool is developed. The coatings provide 1.9 times higher durability of mold parts by compared to the parts without coatings. The technological process of induction cladding on the surfaces of friction nodes parts of wear-resistant antifriction coatings is developed. The service life of bimetallic parts with coatings is 1.25–1.33 times higher than that of serial parts. Physico-chemical principles of creation of aluminomatrix composites were developed on the basis of micro- and ultradispersed oxide powders. This provided a 5-fold increase in tribomechanical properties. In the field of metal forming, the strategy of ring rolling is developed as applied to the nomenclature of rings of the Belarusian enterprises. Technological substantiation is performed for reducing deformations and residual stresses after heat treatment of low-rigid parts such as discs using dynamic stabilization based on alternating cyclic loading.

Evaluating and comparing secondary machining characteristics of wrought and additive manufactured 316L stainless steel

This paper is based on evaluating, analysing and comparing the secondary machining characteristics of wrought and additive manufactured 316L Stainless Steel. This paper is an attempt to determine the process efficiency and evaluate the machinability factors which effect the service life. Stainless steel is a historic iron carbon alloy reputed for its high corrosive resistance and extensive application base. Threading, tapping, reaming and knurling are the most common secondary machining operations after a primary machining operation to achieve a required surface finish and form. As threading plays a significant role in fastening two components together. Threading is selected as a secondary machining operation in this paper. The research methodology consists of conducting threading operation on a hollow cylinder of 50 mm diameter using a lathe. Threads are cut into the workpiece using variable cutting parameters such as spindle speed; 90 and 180 rpm and coolant condition; on/off. Thread pitch which is also the feed rate (1 mm/rev) and Depth of Cut (0.3 mm) remains constant for all the trails. Statistical data are collected and analysed by qualitative and quantitative evaluation. The outputs under consideration to evaluate the machinability includes the cutting forces, thread profile accuracy (pitch) and tool wear. It has been observed that the cutting force and the tool wear was predominantly high for SLM compared to wrought. The paper concludes to convey the point that wrought components has better machinability characteristics than additive manufactured stainless steel.

Molecular Dynamics Simulation Study on the Influence of the Abrasive Flow Process on the Cutting of Iron-Carbon Alloys (α-Fe)

The plastic deformation behavior and microstructural changes in workpieces during ultra-precision machining have piqued the interest of many researchers. In this study, a molecular dynamics simulation of nano-cutting iron-carbon alloy (α-Fe) is established to investigate the effects of the fluid medium and cutting angle on workpiece temperature, friction coefficient, workpiece surface morphology, and dislocation evolution by constructing a molecular model of C12H26 as a fluid medium in the liquid phase using an innovative combined atomic approach. It is demonstrated that the presence of the fluid phase reduces the machining temperature and the friction coefficient. The cutting angle has a significant impact on the formation of the workpiece's surface profile and the manner in which the workpiece's atoms are displaced. When the cutting angle is 0°, 5°, or 10°, the workpiece's surface morphology flows to both sides in a 45° direction, and the height of atomic accumulation on the workpiece surface gradually decreases while the area of displacement changes increases. The depth of cut increases as the cutting angle increases, causing greater material damage, and the presence of a fluid medium reduces this behavior. A dislocation reaction network is formed by the presence of more single and double-branched structures within the workpiece during the cutting process. The presence of a fluid medium during large-angle cutting reduces the number of dislocations and the total dislocation length. The total length of dislocations inside the workpiece is shorter for small angles of cutting, but the effect of the fluid medium is not very pronounced. Therefore, small cutting angles and the presence of fluid media reduce the formation of defective structures within the workpiece and ensure the machining quality.

The use of additive technologies for the restoration and strengthening of parts of transport means

The article is devoted to the comprehensive development and implementation of multifunctional coatings obtained through the use of additive technologies, based on scientific research in the field of restoration and strengthening of worn parts to increase the resource of transport means and their elements, aimed at reducing the material and technical resource and reducing the supply of spare parts. When choosing a method of gas thermal spraying, the main conditions for the formation of high-quality coatings are established, and it is proved that the method of electric arc spraying best meets these conditions. The conducted assessment showed that to restore and strengthen the surfaces of parts of ship's technical equipment, it is expedient to replace expensive powder-coated wires made of highly alloyed alloys with cheaper and more affordable steel wires of a solid cross-section made of iron-carbon alloys. The obtained research results of coatings applied by the electric arc method showed the prospects and feasibility of their processing by pulsed ion nitriding. As a result of the conducted research, for the first time, a method of increasing wear resistance was proposed and developed, which provides an increased level of physical and mechanical properties of restored surfaces and a comprehensive solution to the problems of ensuring the characteristics of strength and operational properties of restored surfaces and developing a technological process of restoring parts of ship's technical equipment.

Research of iron extraction from primary steelmaking slag

The article examines the issue of involving primary steel making slag in the processing with the extraction of iron and the production of slag, which can be used in the manufacture of construction products. Currently, primary steel slag is not used for the production of construction products due to the large amount of iron, and its use is limited to road construction and in most cases, primary slag is sent to landfills. In the Pavlodar region of the Republic of Kazakhstan, during steel production at electric steel making enterprises, the resulting electric furnace slag and dust are stored in slag dumps. They are practically not used, despite their high content of iron oxides and metallic iron particles (up to 40% by weight in some types of slag). The work experimentally determined the chemical and mineralogical composition of primary electric furnace slag with a total iron content of more than 20%. The slag contains the following minerals: wüstite (FeO), magnetite (Fe3O4), gehlenite (Ca2Al(Al,Si)2O7), merwinite (Ca3Mg(SiO4)2). In the course of experimental studies on the recycling of primary electric furnace smelting slags by reduction induction melting of slag-lime-coke pellets, the possibility of extracting iron in the form of iron-carbon alloys and using the slags for the production of concrete was established.