It is shown that the main modifiers of foundry magnesium alloys cannot create heterogeneous crystallization centers in melts during their solidification. Modification of alloy structures is an adsorption‑nanostructural process. It is shown that adsorbed hydrogen is a modifying element of the structures of foundry magnesium alloys. The mechanism of their modification consists in a large decrease in the concentration of adsorbed hydrogen in melts by significantly reducing the concentration of dissolved hydrogen.

In this work, the following studies were carried out: the structure of the starting materials (metal‑powder composition) of heat‑resistant nickel alloys EP648 and VJ159; sphericity, fluidity and bulk density of powder particles from heat‑resistant nickel alloys EP648 and VJ159; elemental (chemical) composition of powder particles of heat‑resistant nickel alloys EP648 and VJ159; the effect of technological and energy parameters of laser radiation on defect formation (pore) in manufactured (grown) blanks (samples); structure formation of manufactured samples from heat‑resistant nickel alloys EP648 and VJ159.

Based on the results obtained, the following were determined: the causes of the formation of satellites on the particle surface of metal‑powder compositions made of heat‑resistant nickel alloys EP648 and VJ159; the causes of the formation of a "layered" and fine‑grained multidirectional structure of manufactured (grown) blanks; the regularities of the effect of the crystallization rate of the melt bath on the total area of defects (pores) in the metal.

It is shown that hydrogen atoms in carbon steel melts are surface‑active elements for aluminum oxide microcrystals. Adsorbed hydrogen atoms reduce the interfacial surface energy and increase the resistance of small aluminum oxide microcrystals to coagulation. To reduce their stability in liquid carbon steels, it is necessary to reduce the concentration of dissolved hydrogen in them. Active modifiers reduce the concentration of adsorbed hydrogen. This enhances the process of coagulation of small microcrystals of aluminum oxide into larger particles that can quickly float in the melt.

The article presents the methodology and results of the study of the effect of ultrasonic treatment of the melt of deformable aluminum alloys during crystallization on the structure and properties of the formed ingots: the dependence of the grain score, porosity, size and distribution of inclusions of intermetallides on the amplitude of ultrasound radiation and the frequency of vibrations, as well as the distance to the waveguide. In addition, data on the analysis of the transformation of iron‑containing phases (α‑AlFeSi and β‑AlFeSi) under the action of ultrasound and dissolution of titanium waveguides during ultrasonic treatment of aluminum melt are presented.

The article presents an analysis of the effect of various special additives on the physical and mechanical properties of sand‑resin mixtures used for the manufacture of cores by the cold‑box‑amine process. Two groups of additives that have the most significant effect on the thermal conductivity of mixtures were studied: additives containing metals or their oxides and carboncontaining additives and composites. The influence of these additives on the tensile strength of the mixtures in the cured state, on their gas content and gas permeability was determined, the results obtained were compared with the characteristics of the reference mixture made without the use of additives.

Foundry sand cores based on organic binders have required tensile, compressive, and bending breaking points, as well as have an excellent knocking‑out ability. However, increased requirements for the environmental friendliness of the foundry have led to a renewed interest in foundry sand cores based on inorganic binders including the sand‑liquid‑glass core‑making technology. Foundry sand‑liquid‑glass cores are significantly inferior to foundry sand cores based on organic binders in terms of a knocking‑out ability due to using a sufficiently large mass fraction of sodium silicate solute to achieve required breaking points of foundry sand‑liquid‑glass cores under tension, compression, and bending, which is accompanied by a deterioration in a knocking‑out ability. Experimental studies aimed at selecting a composition of a sand‑liquid‑glass core mixture, which provides a required compressive breaking point of a foundry sand‑liquid‑glass core in combination with an improved knocking‑out ability, are carried out. Experimental results for destruction of foundry sand‑liquid‑glass cores under compression, which are showing a possibility of achieving a combination of a required compressive breaking point and a good knocking‑out ability, are presented. Ways to increase a strength of a foundry sand‑liquid‑glass core in places of contact with core locks, strengthen the most stressprone areas of a foundry core, and decrease its compressive breaking point by reducing a mass fraction of sodium silicate solute, thereby improving a knocking‑out ability, are considered. Structural robustness test results for foundry sand‑liquid‑glass cores of the investigated composition under compression, as well as an effect of adding a circulating core mixture to the composition on a compressive breaking point are discussed. An effect for inhomogeneities of a foundry sand‑liquid‑glass core on its compressive breaking point is presented. Mathematical expressions for calculating a destruction probability of a foundry core containing an inhomogeneity are obtained.

It is shown that hydrogen is a demodifying element of primary structures of tin and aluminum bronzes during their crystallization. The mechanism of influence of hydrogen on the formation of primary structures of tin and aluminum bronzes can be explained from the position of nanostructured crystallization of casting alloys. Hydrogen atoms adsorbed on elementary nanocrystals in melts prevent the combination of nanocrystals into nuclei of crystallization of microcrystals α‑phases of tin and aluminum bronzes. The result is castings with unmodified primary structures. The modifiers reduce the concentration of adsorbed hydrogen in the melts of tin and aluminum bronzes. This results in the milling of the primary phase microcrystals in the castings as they solidify.

The article considers the results of OJSC “BSW – Management Company of Holding “BMC”, the largest metallurgical enterprise in the Republic of Belarus in 2022. It also presents market diversification and export orientation towards friendly markets. The article describes new types of products and achievements in the field of quality, as well as the functional and operational work of the enterprise’s personnel.

The article considers technological schemes of cold‑formed wire production for bearing rolling elements production. Several technological schemes of wire production are considered. The paper presents a step‑by‑step development of drawing technology of alloyed (chromium) bearing steel grade. Problems arising at drawing of bearing steels are described. The reason of formation of “flaking” on the surface of rod is revealed. Ways of solving the problem of unsatisfactory drawing of wire from bearing steel grades are stated.

Relevance and novelty of technical and technological solutions of the present work are caused by the absence of production of calibrated wire for manufacturing of rolling elements of bearings on the territory of the Republic of Belarus. The development of this type of production will allow to increase the production of high‑tech products with a deep degree of processing (calibrated wire) for the growth of profitability and efficiency indicators. Creation of production of calibrated wire for manufacturing of rolling elements of bearings will allow to reach new consumers of metal products with increase of added value of finished products.

The article presents a new design of a high‑speed small‑size wire galvanizing plant. Electrolytic method of zinc deposition is implemented using two methods of current supply. The quality of the zinc coating was evaluated. Practical recommendations have been developed for the method of applying zinc coating. The new galvanizing unit reduces dimensions compared to existing wire galvanizing units and increases wire pulling speed.

Under the conditions of dynamic impact of high‑speed clusters of powdered micro‑particles on the volume zone of welding between 110G13 and St.10 steel plates, longitudinal strengthening channel elements are formed, and rare earth elements such as lanthanum and cerium are also synthesized.

A study of compositions of samples of high‑strength cast iron, the use of which is possible in the development of an internal combustion engine with an improved design of a combined reciprocating conversion system, has been carried out. A number of research methods were carried out, including isothermal hardening. The optimal combination of strength and plastic properties have samples from high‑strength cast iron containing, wt.%: 2.9–3.1 C; 3.2–3.5 Si; 0.28–0.31 Mn; 0.7 Cu; 0.35 % Mo and 0.025

B. Also, in the course of the study, the possibility was considered and studies were conducted on quenching cast iron in a spray chamber and jet cooling, as an alternative to traditional quenching in molten salts. The data obtained indicate that during jet‑air isothermal quenching, the structure of cast iron is completely and uniformly formed along the cross‑section, while providing a level of tensile strength up to 950 MPa, hardness up to 360–370 NV while maintaining elongation at tension up to 8 %. The use of such a class of cast iron in improved KSPVPP will both increase the life of the internal combustion engine as a whole, and improve its operational characteristics – reduce noise and reduce the weight of the structure.

The working conditions at the workplaces of foundry workers when performing work on the charge sites, production factors determining them are considered. The results of studies of the parameters of the working conditions of the considered professions of foundry workers in comparison with the standard values are presented. It is established that in a comprehensive assessment of the working conditions of workers at the charge sections of foundries, it is necessary to take into account the duration of stay at the working equipment, the equipment and hand tools used, the type of alloy being smelted (steel, cast iron, non‑ferrous metals) and the nature of production.

The working conditions at the workplaces of foundry workers when performing work on core sites, production factors determining them are considered. The results of studies of the parameters of the working conditions of the considered professions of foundry workers in comparison with the standard values are presented. It is established that in a comprehensive assessment of the working conditions of workers in the core sections of foundries, it is necessary to take into account the duration of stay at the working equipment, the equipment and hand tools used, the type of alloy being smelted (steel, cast iron, non‑ferrous metals) and the nature of the production.

The working conditions at the workplaces of foundry workers when working at melting and casting sites, production factors determining them are considered. The results of studies of the working conditions parameters of the considered professions of foundry workers in comparison with the standard values are given. It is established that in a comprehensive assessment of the working conditions of workers at the smelting and casting sites of foundries, it is necessary to take into account the duration of stay at the working equipment, the equipment and hand tools used, the type of alloy being smelted (steel, cast iron, non‑ferrous metals) and the nature of production.

It is shown that the Earth, the Sun and the stars are not inertial systems. The speed of movement of one inertial system relative to another does not affect the parameters of the moving system. Photons, electrons, protons, neutrons move in space in helical spirals. The equations of the special theory of relativity are not applicable to particles that have particle‑wave properties. It is shown that the fifth coordinate is needed for the curvature of the four‑dimensional space of general relativity. Therefore, gravity cannot be interpreted from the position of the curvature of a four‑dimensional space in a four‑dimensional space. In non‑inertial systems, the forces of inertia are not equivalent to the forces of gravity. Photons moving in space in helical spirals with huge rotational frequencies are stabilized in the direction of rectilinear motion. The gravitational field does not affect the energy of photons and the trajectory of their rectilinear motion. The deviation of the trajectory of stellar photons near the Sun is due to the effect of the atmospheric lens of the Sun. The atmospheres of stars absorb photon energy, which is recorded as a red shift in the radiation spectrum. The displacement of the perihelion of Mercury occurs due to the precession of the axis of Mercury’s orbit under the influence of the gravitational forces of the Sun.