The status analysis of the existing foundries of the Republic of Belarus was executed. The share of the use of various technological processes (mold forming methods, melting methods) in the production of foundry products is estimated. The article presents data on volumes produced and imported casting, estimation of total capacity foundries is given. The issues of activity of the working group on optimization of foundry enterprises included in the system of the Ministry of Industry are covered.

Advantages and disadvantages of liquid glass binder are considered. Mechanism of the influence of an ultradispersed modifier on the structure and properties of a liquid-glass binder are submitted. The prospects of using environmentally friendly liquid-glass binder modified with ultrafine materials are justified. The questions of ecological safety of foundry production connected with application of organic binders are described. The advantages and disadvantages of the liquid-glass binder are considered. The mechanism of influence of ultradispersed modifier on the structure and properties of the liquid-glass binder is presented. The prospects of using environmentally friendly liquidglass binder modified with ultrafine materials are justified.

The results of studies on the effect of particles of metal-abrasive sludge used as a potential modifier of gray cast iron are presented in the article.

The influence of metal and non-metal components of the sludge is clarified and the prevailing influence of metal particles is established during the studies. The assumption is made about the mechanism of the effect of particulate additives from the viewpoint of self-organization phenomena in ultradispersed systems. The strength increase of cast iron CЧ20 as a result of the introduction of slurries into the melt reaches up to 25%.

The method of lost foam casting with the reinforcing phase installed inside the polystyrene foam model is considered as a basic technological process. In The new multicomponent systems for the theory of foundry processes will be created in this case: «metal–model–implant–mold» and «metal–reinforcing phase–mold». The influence of the installed macroreinforcing elements in the form of steel rods on the heat and mass transfer was researched, solidification and hydrodynamics is investigated. The process was modeled using the ProCast program by evaluating the solidification conditions in the sand casting mold of cast samples from copper alloys and the reinforcing phase from carbon steel. To compare the results, the process of solidification of cast specimens with a size of 10×200 mm without a reinforcing phase and with a reinforcing phase in the form of rods occupying 20 and 50% of its cross section area was modeled. The research results are presented in the form of graphical curves of the cooling temperature and time. It has been established that the use of a reinforcing phase in a casting mold has a significant impact on the removal of metal overheating due to the consumption of a certain amount of heat for heating the reinforcing phase, increases the rate of alloy hardening and casting cooling.

The prospect of using crystalline fused magnesia (FL LC) in the manufacture technology of melting crucibles by the method of isostatic pressing is shown. It has been established that the production of a material based on MgO using concrete technology is limited to the hydration and loosening of the structure due to the formation and subsequent decomposition of brucite (native magnesia). The physical and mechanical characteristics of the obtained products are given. The effect of the CaO/SiO₂ ratio on the corrosion and erosion resistance of products is considered. The raw material should have a molar ratio of these oxides of more than 1,7. Pressed crucibles were tested in the production of nickel, cobalt and tin based alloys in a vacuum induction furnace. The parameters of operation of products in the enterprise are shown. The effect of clogging by crucible materials during smelting of pure nickel has also been studied. The absence of contamination of the melt with crucible materials such as silicon dioxide, aluminosilicates and oxide films, etc., has been established.

The possibility of the application of impact microindentation method for testing the physic and mechanical properties of cast iron using the IFMH-C instrument developed at the Institute of applied physics of the National Academy of Sciences of Belarus was tested. It was established that the method and the instrument allow to estimate such parameters as Brinell hardness in the range of 100–500 HB, elastic modulus from 40 to 200 MPa, as well as to determine the tensile strength of the flake and spheroidal graphite cast irons. The possibility of using the instrument for non-destructive test directly of parts and products in the manufacturing environments is shown.

The article presents the requirements for the lubricants used in die casting of non-ferrous alloys and polymer materials. The methodology for conducting research to determine the lubricating properties of materials, as well as the results of studies of the lubricating qualities of materials used in the development of lubricant compositions for die casting of non-ferrous alloys and polymer products are presented. It is shown that the use of the materials researched under study reduces the effort to extract the metal rod from the casting by 4.5–8.9 times. It has been established that it is advisable to use petroleum jelly and fus (by-product of vegetable oil) as materials used to develop the composition of a lubricant for die-casting non-ferrous alloys and polymer products. The lubricity of these materials is, on average, 28.8–51.2% higher than that of other lubricants studied.

The influence of the heating rate of a typical case hardening steel 15KHGN2TA and 25KHGT on the growth of austenitic grain during long-term isothermal exposures at the high-temperature chemical-heat treatment was studied. It is shown that the change in the rate of heating case hardening steels in the temperature interval a®g transformations during chemical-thermal treatment has a significant impact on the process of growth of austenitic grains in them.

Regression equations describing the dependence of the average size of austenitic grain on the heating rate, pre-annealing temperature and cementation temperature are obtained, which allow selecting the cementation modes of various steels. A phenomenological model describing the mechanism of formation and growth of austenitic grains in steels under heating at different speeds is developed.

It is concluded that the slow heating of steels in the interval of phase a®g transformation contributes to the formation of a complex of small austenite grains separated by high angle boundaries with adsorbed on them by impurity atoms, which ensures higher resistance grain structure to coalescence and reduce the rate of migration of the boundaries during prolonged hightemperature austenization.

The indicator of the degree of relative reduction of the cross-sectional area and the indicator of the degree of development of the necking, more sensitive to changes in the structural parameters and the deformation temperature of carbon steel compared to the traditional were proposed in comparison with the relative contraction and the true deformation index. The role of relaxation of internal stresses and increased mobility of dislocations in the formation of plastic properties of carbon steel is considered.

The article describes the development of the open joint stock company «Belarusian Steel Works» – Management Company of Holding «Belarusian Metallurgical Company» (BMC) in the field of modern approaches and methods in quality management. The efficiency of their implementation at the BSW is evaluated.

The activities of BSW in this field in 2019 are given. The result of the participation of BSW in the program of Corporate Social Responsibility (CSR) on the platform EсoVadis is shown.. Examples of application of methods by scientists with a world name and successful businessmen are given.

The need described in use and the development of modern management methods at the state level in accordance with the instructions of the President of the Republic of Belarus and the «Complex of measures for 2016–2020 to encourage the introduction in the economy of advanced techniques and modern international systems of quality management in the economy» is shown.

Currently, there is a need to increase the turnover of steel-teeming ladles ESPC-1,2, in connection with which the actual question was to reduce the duration of preparation of steel ladles to work. On steel ladles with a combined lining, one of the solution to this problem is to reduce the duration of drying and heating of the concrete working lining, but there is a risk of «undermining» the concrete mass due to the rapid warming of temperature. During the tests of the concrete mass from the manufacturer «A» for the period 2016–2018 the duration of drying and heating was reduced from 52 to 37 hours. Average overhaul life and durability of the concrete lining has increased by 37% and amounted to 96 meltings.

Almost all metal at OJSC «Byelorussian Steel Works» – management company of holding «Belarusian Metallurgical Company» includes today a mandatory physical-mechanical tests which allow to estimate the parameters of the raw materials, to know the reasons for loss of strength and determine operational characteristics. In the Central Factory Laboratory (CFL), laboratory of physical and mechanical tests (LPMT) for the preparation of samples of reinforcement equipment is used of knives in the cutting machine SIMA GEL-30 for cutting rebar from the mill 320 rolling shop № 1 with a diameter from 6 to 24 mm. In the drop-hummer shop annually discards off for scrap waste up to 50 knives. Hydraulic shears of drop-hummer shop used knives set of production of OJSC «Kobrin tool plant «SITOMO», made of steel grade 30ХСНВФА, according to the TU14-1-4461. The staff of the Central laboratory LFMI proposed to use waste knives drop-hummer shop for the manufacture of knives for the chopping of the machine SIMA GEL-30. On the basis of the conducted researches the technological scheme was developed for production of knives for the chopping of the machine SIMA GEL-30 cold cutting of reinforcing bar mill 320 the rolling shop № 1.

The development of the world automotive industry is aimed at creating new, both in design and properties of tires that can operate in high dynamic loads under different operating conditions. The most probable cause of aging of automobile tires is considered in the article; one of methods of laboratory tests for the accelerated aging of system rubber-metal cord is described. The dependence of the influence of the metal cord design on the adhesion characteristics of the rubberized metal cord and its resistance to aging is also analyzed.

To ensure safe operation of buildings and structures from reinforced concrete, European norms set requirements for its fatigue strength (resistance). Tests are carried out with oscillation swing amplitude 2sa from 150–200 MPa. Rebar shall withstand from 1 to 2 mln. cycles.

The analysis of causes which decrease the fatigue strength of cold-formed steel is made in the article. Fatigue strength is a lot affected by surface defects and stress concentrators. Filler transition in the point where transversal rib crosses a rebar body becomes as a rebar stress concentrator. To detect details of early breakage, analysis the condition of fracture in the area of thickened (marking) ribs was made. Sequence of rebar breakage was established as well as the initial point of a crack creation was detected. This fracture is characterized as a fatigue one, with clear zones of fatigue fracture having fine-grained surface and static fracture zone– the rest of section with fibrous structure. While applying a bar mark, smoothness of filler transition was disturbed in the crossing point where transversal rib crosses a rebar body, and this action caused decrease of fatigue strength of cold-formed rebar.

The article describes research on development of requirements for rolling tools used in production of cold-formed rebars.

Use of information given in this article during design, purchasing and manufacture of the equipment will allow to minimize factors which have negative influence on rebar’s fatigue test results.

Technical measurements of linear-angular sizes of parts and products are the most common in mechanical engineering and make up to 95% of the measurements of all controlled sizes. Measuring control is an integral part of each operation of technological processes of production, assembly, testing of products. The complex method of measuring the external and internal geometric characteristics of a carbide die, given in the article, allows to measure the geometric parameters of small-size parts and to give a final assessment of the product for compliance with the requirements of the project technical documentation.

The possibility of application of the double finishing drawing die at the stage of fine-drawing in the manufacture of steel metal cord 2x0 30SHT is сontemplated. As a result of the performed studies, a numerical finite element model of wire drawing in a serial finishing single fiber and in an experimental double finishing fiber has been developed. The obtained distribution of effective plastic deformation in the wire during drawing shows that when drawing in a double fiber, there is a higher uniformity of deformation in the direction of the radius of the wire along the cross section located at the outlet of the die. The distribution of effective stresses in the wire when drawing shows that when drawing in a double fiber, there is a more uniform distribution of effective stresses in the direction of the radius of the wire along the cross section located at the outlet of the die.

Further experimental tests performed at the drawing mill NT 12.4 in StPC-1 showed that the use of double dies allowed to increase the plastic properties of the wire 0.30 SHT, manifested in technological tests by increasing the number of reversible twists of the wire from 7 to 78 and reducing the ratio of yield strength to tensile strength decreased from 95 to 91.

The work is devoted to solving the axisymmetric problem of the theory of pressing porous bodies with practical application in the form of force calculation of metallurgical processes of briquetting small fractional bulk materials: powder, chip, granulated and other metalworking wastes. For such materials, the shape of the particles (structural elements) is not geometrically correct or generally definable. This was the basis for the decision to be based on the continual model of a porous body. As a result of bringing this model to a two-dimensional spatial model, a closed analytical solution was obtained by the method of jointly solving differential equilibrium equations and the Guber-Mises energy condition of plasticity. The following assumptions were adopted as working hypotheses: the radial shear stress is equal to the tangential one, the lateral pressure coefficient is equal to the relative density of the compact. Due to the fact that the problem is solved in a general form and in a general formulation, the solution itself should be considered as methodological for any axisymmetric loading scheme. The transcendental equations of the deformation compaction of a porous body are obtained both for an ideal pressing process and taking into account contact friction forces. As a result of the development of a method for solving these equations, the formulas for calculating the local characteristics of the stressed state of the pressing, as well as the integral parameters of the pressing process are derived: pressure, stress, and deformation work.

The study of the effect of hardering temperature on the properties of beryllium bronze in subsequent aging were made. It is shown that the elastic properties of the aged material, with the hardening is carried out from 750 °C, significantly lower than hardering from 760 °C. With the increase of quenching temperature, this difference decreases after quenching from temperatures 770–800 °С with the level of hardening of the alloy during subsequent aging is practically the same. Comparative studies of the structure and properties of elements heat – treated under different conditions (furnaces with controlled air atmosphere, vacuum containers, molten salts). It is established that the main reason for the shrinkage value is the difference in their structural state caused by the unequal heating time of the material to the aging temperature.

The regularities of the formation of powders based on the Fe-Al system, obtained by the method of mechanical alloying and intended for the deposition of thermal spraying coatings were established. The morphology, structure, phase composition and properties of materials are investigated. After mechanical synthesis, the powders have an average particle size of 30–100 µm, submicrocrystalline structures, and nonequilibrium phase composition. Annealing of powders causes to an increase in the hardness of particles up to 80%, the value of which is largely preserved after prolonged heating to 1170 K, which indicates the presence of heat-resistant materials.

Polymeric materials are mainly dielectrics. The use of protective clothing made of such materials may occur accumulation of static electricity. The electrification of materials creates a fire hazard in the presence of dust and various gas mixtures. For reducing the accumulation of static electricity charges on the surface of protective clothing carried out the modification of polyethylene terephthalate by clusters of steel 12X18H10T. Modification was carried out in a vacuum using stationary metal plasma source operating in the mode of separations. The process was carried out by alternating periods of the source plasma (1 minute) and pause for tissue cooling (1 minute).

The results of the study of the surface morphology of polyethylene terephthalate steel coated fabrics and magnetic resonance absorption measurements of microwave energy is given. The main regularities of the magnetic-resonance absorption spectra are revealed. Method of electronic magnetic resonance (EMR) found that the spectra are inhomogeneous broadened broad lines with effective g-factor value of 2.2±0.1 and the line width of 110.1 mTl. It was found that the non-resonance absorption of the electromagnetic field of microwave is insignificant.

Based on the data on the chemical composition of cemented steels produced according to the European standard EN 10084, the calculation of their hardenability by different methods was carried out. The use of methods is justified by comparing the results of the race with the experiment. The assessment of applicability of the analyzed steels for gears of transmissions of domestic mobile machines is carried out. The classification of cemented economically alloyed steels with chemical composition according to EN 10084 norms according to the criterion of hardenability is developed, according to which these steels can be divided into 4 groups according to the applicability for transmission gears of domestic automotive technology: for gears with a module of up to 4 mm, up to 5 mm, up to 8 mm and up to 10 mm.

The chemical and grain-size analysis of zinc dust – waste of hot – dip zinc plating were made. The research results showed that zinc dust is a dispersed waste with particles of mainly circular shape and sizes from 3 to 200 microns, and in chemical composition it mainly meets the requirements of ISO 3549. The presence of lead in the zinc dust composition, which is slightly higher than the acceptable level will be taken into account in the development of zinc-rich paints compositions. Analysis of the results of sieving of zinc dust showed that it contains particles of size £15 µm, which is about 27% of its fractional composition and which can be recommended for the manufacture of zinc-rich paints.

The results of the study of working conditions working in electroplating shops. It is shown that the main production factors of working conditions are noise, vibration, dust, gas contamination, relative humidity of air, the severity and intensity of the labor process. The results of the studies have shown that at all workplaces there are exceeding of the permissible values for noise level, the content of harmful substances in the air of the working environment when working directly with the galvanic baths, the relative humidity of the air. It is noted that the work performed on the severity and intensity of the labor process can adversely affect the health of workers.

The results of studies of the factors of the production environment in the workplace in the performance of welding works to eliminate casting defects of castings and measures to protect workers from their impact are researched. It is established that in the workplace of welders there are increased levels of noise in various welding methods, as well as when stripping welds with a hand tool; increased levels of local vibration when working with hand grinders; exceeding the permissible values of the intensity of infrared (thermal) radiation. The results of the study of ultraviolet radiation in various welding operations.