The annual and prospective increase in the cost of resources (material and energy carriers) leads to an increase in the cost of cast blanks, the cost of machine tools and a decrease in their competitiveness. The directions of thrift of basic and auxiliary materials, reduction of machine tool manufacturing time due to a revolutionary approach to the principles of design and creation of basic parts from unified modular cast blanks are proposed.

It has been shown that elementary crystalline cells of graphite and basic products of iron modification do not correspond to the principle of structural and dimensional correspondence of Dankov –Konobeevsky. Modifying elements Al, Ca, Mg, Ba, Ce increase the phase tension melt‑graphite by binding surface‑active oxygen and sulfur. Modifying cast iron eutectic graphite is a nanostructured process in which modifying elements refine elemental graphite nanocrystals from adsorbed oxygen and sulfur atoms. This contributes to an increase in the concentration of graphite nuclei upon solidification of the cast iron melt. The modification reduces the concentration of dissolved hydrogen, which increases the effectiveness of the modifying effect. Reduced concentrations of demodifying surface‑active elements, melt degassing, increased heat removal contribute to increasing the degree of branching and compactness of graphite dendrites during iron crystallization. The strongest modifying element of eutectic cast iron graphite is magnesium.

It has been shown that the elementary crystal cells of the basic products of deoxidation and modification of carbon steel, δ ferrite and austenite do not correspond to the principle of structural and dimensional correspondence of Dankov – Konobeevsky. Modifying elements Ba, Ca, Mg, Ce, Al increase the surface energy of the iron‑carbonaceous melt by binding surface active oxygen. Deoxidizers combine dissolved (free) oxygen into oxides, and modifiers – adsorbed oxygen. Steel modification is a nanostructural process in which modifying elements refine elemental iron nanocrystals from adsorbed oxygen and hydrogen atoms. Modifying elements reduce the concentration of dissolved hydrogen, which contributes to the modifying effect. The strongest deoxidizer and modifier of carbon steel is magnesium.

The distribution of the castings production in the world, whose total output is more than 112 million tons, is considered. A steady trend to the replacement of rolled alloy steel, which is used for critical engineering products, by Austempered Ductile Iron (ADI) is outlined. The latter is ductile cast iron with globular graphite, which is austempered (isothermally quenched) to produce ausferritic (bainitic) structure. The dynamics of prices for main alloying elements in ADI (molybdenum, nickel and copper, whose total amount in the alloy reaches 5 %) is considered and their steady growth is outlined.

The research goal is to develop a concept of economical alloying of ADI (the total content of Mo, Ni and Cu should not exceed 2 %) retaining sufficient hardenability and substantially decreasing the cost price. The goal is attained by decreasing the content of the most expensive alloying element, molybdenum, to a minimal level along with the use of microalloying and applying one of the methods of hot plastic deformation to the casting.

The reduced content of the main ‘triad’ of alloying elements is compensated by microadditives of strontium or barium, vanadium, boron, niobium and the addition of misch metal. Several groups of economically alloyed cast irons are proposed: (1) low‑nickel and low‑molybdenum with increased content of copper (up to 1.8 %) and the addition of vanadium, (2) molybdenum‑free with microadditive of boron, (3) molybdenum‑free with microadditives of niobium and boron, and (4) molybdenum‑free minimally alloyed with nickel and copper.

It is shown that plastic deformation, along with giving the product the required shape, affects the kinetics of structural‑phase transformations. and acts similarly to alloying with Mo and Ni, shifting the TTT‑curve to the right. Therefore, the ausferritic structure can be obtained at a lower cooling rate.

The mechanical properties with such alloying and the use of plastic deformation are the following: ultimate tensile strength 1100–1500 MPa and elongation to failure 2–4 % for lower bainite; ultimate tensile strength 800–1100 MPa and elongation to failure is 4–7 % for upper bainite.

The article presents an analysis of the formation parameters of the microrelief of artistic casting. The direction for solving particular issues of improving the castings quality with high requirements for the accuracy of the surface relief is shown.

It has been shown that the elementary crystal cells of the basic products of modification of silumins, aluminum and silicon do not correspond to the principle of structural and dimensional correspondence of Dankov – Konobeevsky. Modifying elements B, Sr, P significantly increase the surface energy of liquid silumins, and Zr and Ti practically do not affect it. Modification of silumins is a nanostructured process. Ti, Zr, B form intermetallides that refine aluminum nanocrystals from demodifying adsorbed hydrogen atoms. Phosphorus, atomically dissolving in silumin, refiners silicon nanocrystals from adsorbed oxygen. Na and Sr form an emulsion and colloid in liquid silumin, which protect eutectic microcrystals of α‑and βSi‑phases from demodifying molecular hydrogen. All these processes increase the concentration of crystallization centers of dendritic microcrystals α‑and βSi‑phase, make them more branched and compact.

The article describes the conducted research of the product “round flat‑link chain”, with the rupture of three links after heat treatment and mechanical tests at the consumer. The purpose of the research was to determine the cause of the destruction of the chain links. Visual inspection of the chain revealed breaks in three of the nine links. The rupture occurred in the area of factory branding. A metallographic study of two samples cut from a chain link with a break and a link without a break was carried out. During the study, a surface layer was found that was distinguishable from the main microstructure. The presence of the detected surface layer is due to surface hardening. The hardened area of the surface of the link with a break is almost two times smaller than in the link without a break. The amount of residual austenite is larger and larger in the link with the gap. As a result of the conducted studies, it was found that the destruction of the chain links occurred due to a violation of the heat treatment regime of the surface layer.

When controlling the length of the yield site, the influence of the ferrite grain size, the amount of perlite, temperature, speed and deformation scheme on the localization of low‑carbon steel plastic deformation, which reduces the ability of the metal to deformation hardening, is considered.

Welding wire used for welding metal structures must have high technological and mechanical properties, since it is the main material that provides the required chemical composition and properties of the metal of the welded seam of structures. This article describes the experience of producing wire rods made of steel grade Sv‑08G2S for the subsequent production of welding wire in the conditions of OJSC “BSW – Management Company of Holding “BMC”. The technology of welding wire production in the conditions of mill 150 has been developed with heat treatment of the produced wire rod to give it the required plasticity and subsequent processing in hardware production into welding wire. With the construction of a new modern small‑grade wire mill 370/150, the developed technology of welding wire production has been improved to obtain maximum plasticity of the initial wire rod in order to exclude all types of additional heat treatment at the hardware conversion due to the choice of a rational chemical composition of steel and the formation of a favorable microstructure of metal. The wire rod obtained as a result of the work has been successfully processed in hardware production into copper‑plated welding wire without additional heat treatment.

Predicting the physical and mechanical properties of thin wire and metal cord will ensure an increase in the quality of latuned thin wire, a reduction in the number and time of technological pauses, and increase the manufacturability of metal cord twisting. Considering that the deformation manifests anisotropy of the properties of thin wire, the prediction of physical and mechanical properties and the degree of unevenness of deformation becomes an urgent task.

The paper studies that an increase in the drawing speed of a thin wire leads to the acquisition of a more uniform and fine‑grained structure. The dependences of the physico‑mechanical properties of thin latuned wire after the metal cord is twisted on the speed of fine drawing are developed. The effect of the deformation rate on the microhardness of a thin steel wire is investigated. It is determined that in order to increase the productivity of metal cord twisting, it is necessary to bring the dependence of the increase in hardness and equivalent stresses in metal cord wires to a linear form by changing the speed of the twisting at its individual stages. For practical use, the dependences of the mechanical properties of a thin wire of strength class HT on the drawing speed are derived.

During the analysis, the results were obtained, which are applicable in the design of new or modification of existing routes for drawing thin wire, as well as in the design of new metal cord structures.

The paper analyzes the existing technologies of metallurgical production with minimal harmful effects on the environment. Emissions of carbon dioxide into the atmosphere can be eliminated using hydrogen as a reducing agent with iron oxide. The best results are realized when hydrogen is produced by electrolysis of water, but such technologies require serious investments. More realistic in terms of creating “green” technologies in metallurgical production is to reduce the consumption of natural gas, capture waste gases of metallurgical production and use them to produce electricity and new types of products: methanol, synthetic alcohol, fertilizers and polymers. An integral part of “green” technologies is also the implementation of the NoWASTE concept, aimed at minimizing waste to be disposed of. Examples of non‑waste technologies for the processing of aluminum waste at OOO NPF Metallon are given.

The features of the editing technology, possible defects of sheet metal and piece blanks of complex configuration are presented. The main schemes and designs of sheet‑straightening machines are considered, as well as the main directions of improvement of LSM designs and editing technologies are highlighted. The analysis of the process of roll straightening is presented taking into account the phenomena occurring in a metal undergoing alternating loading with decreasing amplitude (interaction of elastic and plastic deformation, Bauschinger effect, etc.). The parabolic dependence of the residual curvature on the yield strength is noted. The obtained data were used in the design of the roll straightening complex and the technology of straightening sheet blanks of complex configuration.

The paper considers the theory and practice of obtaining cast composite materials, their classification and features of the formation of the structure during their synthesis. The results of obtaining parts of responsible purpose from cast composite materials are presented. It is shown that the formation of the transition zone occurs during the infiltration of the matrix melt, followed by its growth during exposure at the synthesis temperature.

The processing of salt slags in aluminum production in order to obtain a powder material with a high content of aluminum oxide phases and the results of thermodynamic assessment of the hydrolysis reactions of aluminum carbide and nitride during the hydraulic treatment of slags are discussed. It is reported that water‑soluble fluorine compounds, such as Na₃AlF₆, CaF₂, MgF₂, K₂ZrF₆ , in the composition of refining fluxes complicates the processing of aluminum slags, which involve leaching of salts by water. A rational solution seems to be the replacement of sparingly soluble salts in refining fluxes with sodium or potassium fluorides with a higher solubility in water. It is shown that the powder mixture obtained after hydraulic treatment of aluminum slag includes various forms of structural components in the form of films, shells, submicroand nanostructures of various morphologies with the participation of various types of nano‑components, in which the phases of non‑metallic compounds predominate, mainly ceramic substances and salts (corundum Al₂O₃, aluminum oxynitride Al_2.85O_3.45N_0.55, aluminum nitride AlN, sodium chloride NaCl) and metallic aluminum. It is indicated that the possibility of forming eutectic mixtures of ceramic compounds of aluminum oxide and aluminum oxynitride, which are more fusible than pure oxides and nitrides, must be taken into account when developing salt slag recycling technologies in order to obtain ceramic powder materials with a high content of alumina phases.

Using the example of the process of obtaining semi‑finished components of knee joint endoprostheses, the stages of obtaining a complex profile forging are demonstrated. A comparative analysis of obtaining the same product from different alloys is given. The methodology is given and the results of determining the energy‑power parameters of hot volumetric stamping of hard‑to‑form VT1–0 and Co‑Cr‑Mo alloys are presented. A typical scheme of the technological process of manufacturing forgings with an elongated axis and significant thickness differences characteristic of endoprostheses is determined.

The influence of the beam current, the distance between the beads of the clad material and the wire feeding intensity during electron‑beam (EB) surfacing of titanium alloy VT9 on the thickness and uniformity of the resulting restoring coating was investigated. As the beam current strength increases, the width of the deposited layer increases and the height decreases. The optimal distance between the beads should be considered an offset that does not exceed the width of the bead. It is possible to control the height of the deposited layer in a wide range by precise dosing of the wire feed intensity. The uniformity of surfacing is ensured by a balanced energy impact. Chemical composition of the clad layer meets the requirements of normative documents on the content of impurity gases for products from medical materials, obtained by additive technologies. The results of the study are used in the restoration of the surface of the landing gear element of aviation equipment.

The results of studies of Co‑Cr alloys for biocompatible medical products are presented. The article shows that alloys of CoCr‑W system are promising for the manufacture of coronary and vascular small‑sized stents with high radial rigidity of the structure. Ensuring the corrosion resistance of the material is one of the general requirements for implants of the Co‑Cr alloys. The main influence on the corrosion resistance, biocompatibility and mechanical properties of coronary and vascular implants subjected to increased cyclic loads is exerted by the state and structure of the surface of the Co‑Cr alloy. Effective ways to change the surface structure and improve the properties of Co‑Cr alloys are heat treatment processes, including those in vacuum, mechanical and electrochemical methods of surface treatment.

The article presents information on model plastics presented on the market of the Republic of Belarus. The analysis of methods for creating accurate model sets using both 3D printing from thread and granules, and obtaining model sets from an array of model plastic using 3D milling is carried out. The properties were evaluated and the behavior of glued and solid plastics under compressive loads in the longitudinal and transverse directions was shown. Economic efficiency assessment of various methods of obtaining model sets is given, based on a comparison of the cost of materials and the production process itself.

The technology of thermocyclic treatment of fine‑module gears has been improved, which makes it possible to increase their wear resistance by 30–40 %. Gears were subjected to preliminary cyclic heating and subsequent impulse hardening. In all cases of hardening, a martensitic structure is formed, which provides high rigidity of the material. The sizes of martensitic plates depend on the heating temperature during quenching. During cyclic heat treatment up to a temperature of 450 °C, the sizes of austenite grains and martensite plates did not depend on temperature.

Based on the empirical data, specific rates of ecological tax for the emission of pollutants into the atmosphere, approved by the tax code of Belarus and thermodynamic calculations the approximate specific ratio of hydrolysis products and products of their thermal oxidation, formed by exposure to humid atmosphere on the aluminum slag was determined.
The work shows that the damage from atmospheric pollution by an aluminum recycling plant with a capacity of 200 thousand tons can be from 0.66 to 52.7 million U.S. dollars, that is, depending on the territorial location of the pollution source for the same substance, the damage may be increased by up to 80 times.

The content of harmful substances in the air is an important parameter of the working conditions of foundry workers. Due to the peculiarities of the technology, there are many sources of intense dust emission in the foundry. The distribution of dust concentrations in the atmosphere of the workshops was determined from the equation of the dust balance in the workshop room. The possibility of obtaining by calculation an objective picture of the distribution of dust in various sections of foundries is shown. Data from various studies were used to determine the density and dust at various sites of foundries. The results of the theoretical calculations show that in foundries, dust capture is an effective means of reducing the dustiness of the air of working areas.

The issues of the activities of the Council of the Research and Production Center of OJSC “BSW – Management Company of the Holding “BMK” – NAS of Belarus aimed at solving the problems of the enterprises of the holding, the proposals of the heads of “BSW”, scientific institutions of the NAS of Belarus and universities of the country to assist in their solution are highlighted. The issues of scientific and technical activity, equipping the enterprise with modern equipment are considered. The results of the work on the harmonization of European and republican standards are presented, as a result of which the harmonized international standards STB ISO 683‑1‑2020, STB ISO 683‑2‑2020, STB ISO 683‑3‑2020 were developed for the first time, passed all approvals and entered into force in the Republic of Belarus, a new improved metallurgical technology for smelting, out‑of‑furnace processing and rolling of steels corresponding to international standards was developed. The environmental problems of the enterprises of the BMK holding related to the disposal of waste generated at the enterprise were discussed. Methods and ways of their processing and utilization are considered.