In the existing theories of liquid state of metals and alloys the basic structural element is atom. It creates a serious problem in scientific understanding of the mechanism of process of melt and properties of metal melts. For the solution of this problem it is necessary to consider that the basic structural element of liquid metals and alloys is the nanocrystal. As a result of researches it was set that metal melts are the equilibrium two-phase systems consisting on average of 97% from nanocrystals and of 3% from atoms, which form an unstructured zone.

Resin in sand-resin mixes in the course of heating at production of casting shell molds undergoes changes of a state: solid – liquid – solid. For the purpose of increase in durability and decrease in contents of binding (pulverbakelit) in mix when forming a shell, along with thermal influence, the static pressure, the resines changing in compliance with change of aggregate state was used. Basic pressure is 0.25 MPas and moves through a press plate right after filling of mix on heated up to 230 °C model plate. In 10 seconds pressure increases up to 0.35 MPas. And in 10 seconds pressure goes down to 0.2 MPas. It is experimentally defined that the castings received in the shell forms made with use of variable pressure have the minimum and uniform internal tension. Also researches showed that such castings have high purity of a surface (Rz 70–80) and lack of internal defects.

It is shown that the main technological problems of modifying of structure of silumin castings are: absence of the universal modifiers, limitation of their action in time; saturation of a melt by hydrogen and oxide of silicon. Admixture modifiers do not solve these problems. These problems could be solved by method of hereditary modifying. For this purpose it is necessary to use the silumin castings with a high-dispersible microstructure received by casting in a crystallizer with a high speed of cooling.

The basic requirements for cast blanks and details of agricultural machinery are considered. The prospects of using the method of centrifugal casting in the production of workpieces for the repair and maintenance of agricultural machinery in Belarus are shown. On the basis of the analysis of a number of details of the agricultural machines having the sufficient program of production the choice of the equipment for centrifugal casting of JSC BELNIILIT’s design was selected.

It is shown that intermetallic metals of the modifying ligatures are not the crystallization centers of primary crystals of a a-phase. As the main demodifier serves hydrogen dissolved in liquid silumin. For a solution of the problem of modifying of primary crystals of a a-phase in castings from silumins it is necessary to accept a presumption that crystallization centers of primary crystals of a a-phase are the crystalline developments consisting of a-phase nanocrystals, and the role of the modifying intermetallic metals of modifiers comes down to the active absorption of the dissolved hydrogen.

The work is devoted to solution of the actual problem to increase the service life of blade mixers used in the foundry industry. The existing methods for ensuring wear resistance of mixing blades are described, their advantages and disadvantages are indicated. Based on the analysis of scientific publications a technical solution for applying protective coatings to the blades of the mixer using gas-thermal spraying has been proposed. The results of laboratory studies of the wear rate of gas-thermal coatings from various powder mixtures of the Ni-Cr-B-Si system under conditions of abrasive wear are presented. The results of operational tests of experimental products under conditions of corrosion and abrasive wear during the operation of a paddle mixer are given. The composition of the powder mixtur ensuring maximum wear resistance of the mixer blades was developed.

It is shown that the phosphorum which is contained in a silumin melt in number of 0,01–0,04% exists in the dissolved form. For a solution of the problem of modifying of primary crystals of a β -phase in silumin castings it is necessary to accept a presumption that the oxygen adsorbed by a melt promotes decay and hinders the formation of crystallization centers of primary crystals of a β -phase. The role of phosphorum comes down to reduction of concentration of the adsorbed oxygen which works as the demodifier of primary microstructure of castings.

The data on the history of the formation and development of forging and blank production, reorganization of departments and sections of the forging plant at OJSC «MAZ» are given. The technologies of shaping and forging used in press – forging and thermal equipment are described. The main measures to ensure the production volume and quality of forgings are listed, improvement of working conditions and environmental conditions at the plant are shown. A brief description of the means of mechanization and automation of technological processes of forgings manufacturing with the use of induction heating created at MAZ is given. Prospects of development of blank production are considered.

Drawing region ultralarge total of reductions with the prevailing influence of compressive stress provides relaxation local peak stresses and increase of the stock of plasticity ultraviolence brass plated wire for steel cord.

Dynamics of development of sales of cars in the world is considered. The steady growth of car sales in the period 2013–2018 was determined. It is determined that in just nine months of 2018, 71 153 025 cars were registered in the world, which is 1.7% more than in the nine months of 2017, and according to the data of the ASEAN (European Association of car manufacturers), 11 951 957 cars were registered in the automotive market of the European Union countries in the nine months of 2018 in the EU, which is 2.5% more than in the same period of 2017. It is determined that despite some decline in production in Japan, South Korea, the rest of the traditional car manufacturers in Europe and North America show a steady pace of development, built and planned construction of new modern production of automotive equipment mainly in the Asian and South American regions. Analysis of the development of metal cord production showed that it is expected to increase investment in the production of metal cord with a planned increase in production by 22% until 2022. At the same time, the greatest growth should fall on passenger and lightcargo tires. Due to the increasing competition in the metal cord market, the development of the latter is in the direction of highstrength structures. The transition to a high-strength metal cord attracts the possibility of reducing the weight of tires, increasing their mobility and reducing the cost per unit weight of the metal cord with an equally strong replacement of structures in tires.

Rolling is the final stage of the metallurgical cycle and has a great influence on the quantity and quality of products, as well as on various technological and economic indicators of the plant.

The OJSC « BSW – Management Company of Holding «BMC» is working on the development and supply of hot-rolled round products for the automotive industry in Western Europe.

The increasing requirements for the quality of the surface of hot-rolled steel are a powerful incentive to improve the technology of its production, which is impossible without the use of modern methods of control and proper identification of detected defects.

The article presents the results of the study of defects of hot-rolled products of rolling mill № 1 850, having the rolling nature of formation.

Metallographic study was conducted on the basis of: visual inspection of defects, in some cases with the preparation of a template for the study of macrostructure and location of defects; analysis of images of the microstructure of the cross section of the sample in the area of defects. With the help of characteristic external and microstructural features of defects, special etching in reagents, the causes of their formation were established, and recommendations for their minimization or complete elimination were proposed.

This article describes a version of the modernization of the software (SOFTWARE), which allows to create monthly production plans and shipping program for shops of the main production, which used some of the mechanisms of object-oriented programming. The result of this work was the unification of the same actions in the formation of monthly plans for different shops within the framework of this SOFTWARE, the use of the same objects in different parts of the SOFTWARE with rapid adaptation to specific requirements in this place, the possibility of using the obtained objects in the newly developed provision by various departments of development.

The article presents a method for determining the residual strain in the steel wire cord of construction 3x0,30. The causes of residual strain, the effect on the quality of finished product and the determination of the degree of residual strain by chemical method are considered. The cause of residual strain is uneven plastic deformation of a solid body due to various changes in different places of its length and volume. Residual strain of steel wire cord are made up of stresses existing in the wire after drawing, and the stresses created during the lay of wire.

An important task in the framework of the metal wire cord manufacturing technology, which is faced by specialists at «BMW» – the Management Company of the Holding «BMC» is to reduce residual strains at all stages of metal wire cord manufacturing. Residual strains are an additional factor affecting the adhesive strength and durability of adhesive joints.

The principle of determining the residual strains is to remove the coating from the metal wire cord, paint the transverse halves of each thread. Then the filaments are impregnated with nitric acid, and the residual strain on the surface is recorded as the difference between the residual strains of the two halves of the wire.

High pressure hose (HPH) is a flexible pipeline for the transportation of special hydraulic and motor fluids based on mineral oil, liquid fuel, grease or water emulsion under pressure, to transfer the working force. Structurally, the sleeve is two or more rubber tubes placed one into the other, reinforced with metal braids or coils, equipped with connecting fittings [1]. HPH is characterized by a sufficiently high flexibility in combination with the ability to withstand significant pressure.

In cases of premature failure of high-pressure hoses during cyclic or impulse tests, the cause of the nonconformity must be determined. The article describes the main stages of the study of defective high-pressure hoses in determining the cause of their failure and provides examples of studies using visual, metallographic, electron microscopic methods of analysis in the metallographic laboratory of OJSC «BSW – Management Company of Holding «BMC».

Relevance: the increase in the number of destruction of welded joints of the metal wire cord due to discrepancies in the microstructure of the welded seam.

Purpose: to find the roots of defects in welded joints of metal wire cord to reduce the number of inconsistencies in this parameter and study the features of the formation of the microstructure of welded joints.

Methods of research: as a material for research the metal wire cord of various designs made in steel – wire shop No. 2 of OJSC «BSW – Management Company of Holding «BMC» – a rod of own production was applied; the study was conducted using a Nikon SMZ 1000 stereoscopic microscope with a video system and an inverted metallographic microscope OLIMPUS GX-51 with a video system; measurement of hardness was carried out according to Vickers with a load of 0.5 kg on a hardness testing ZWICK 3Х5624АТ.

Research results: the regularities and causes of the formation of mismatch of the microstructure of welded joints during welding on metal: incorrect setting of the welding machine (slowing down of the welding carriage); mismatch of the tempering temperature (a faulty button or operation home run twice); a small dwell time in the terminals (jaws) for tempering; inadequate execution of Regulation of the welded connection of the operator’s actions (pass or failure of the operation «tempering of the weld»); influence of external environmental factors (microclimate) of the operator’s workplace.

The paper presents a thermophysical analysis of modifying the surface of a workpiece by laser radiation due to the melting of a layer of a doping substance previously deposited on the surface of the base metal.

The process of heating a two-layer metallic system with a laser pulse with a normal distribution of power density over the beam section is considered. Under the action of a heat source of constant power, moving in a straight line at a constant speed, the process of heat propagation tends to the limiting quasistationary state, when the temperature field does not change with time and moves along with the source.

The dependences obtained allow us to estimate the effect of the laser treatment mode on the distribution of temperature fields, establish the patterns of heat propagation and relate them to phase transformations in the metal.

It has been established that the technological modes of exposure to laser radiation are limited by the value of the energy per pulse from 4 to 12 J. The choice of technological modes of exposure is determined by the combination of the scanning speed of the laser beam and the radiation power.

The article briefly discusses the capebilities of modern metallography – optical contrasting, quantitative metallography, image processing programs. The question of the absence of modern literature on metallography is touched on. The problem of representing the structures of materials and the Internet is discussed. The problems of the development of metallographic research in Belarus are also presented. It is noted that the development of metallographic research in Belarus is hampered by the lack of funds for the acquisition of the equipment, as well as the lack of qualified personnel.

Exposure to laser radiation leads to a change in the temperature field of the substance being treated. The nature of heating, which is determined by the rate of change of temperature, temperature gradients, the time to reach the temperatures of structural and phase transitions, is different depending on the properties of the material being processed and the processing conditions.

When modifying the surface layers by high-energy processing by changing the power and time of exposure to laser radiation, you can get a wide range of structural states of the treated surface areas of the material.

It is shown that the shape of TVP diagrams and cooling curves of precision alloys on the surface of a two-layer metal system after heating them with laser radiation are determined by the competition of two processes acting in opposite directions: an increase in the driving force of the crystallization process with an increase in supercooling and a decrease in the surface of atoms.

The method of surface modification by moving laser radiation allows to obtain amorphous functional layers of precision alloys on the surface of metal products.

The possibilities of measuring the depth of the surface relief on metallographic microscopes manufactured by OJSC «Optoelectronic systems» are illustrated. For the microscopes MI-1 and MICRO-200 a technique for determining the height of the relief is considered, which is based on the relationship between the angle of rotation of the drum tincture of precise focus and vertical movement of the object table. Examples of crater depth measurements after exposure to laser radiation on a metal surface are given. For MI-1 and MICRO-200 microscopes, the depth of the well was determined as 99.36 and 99.8 µm, respectively, which is consistent with the profilometer data (~100 µm). For a plane-parallel quartz plate, the measurement results were 0.435 µm when determined microscopically, as well as the object-micrometer. The possibility of determining the thickness of titanium nitride coatings by differential interference contrast is considered. The method allows the determination of the thickness of the difference in interference colors, if the image areas are at different heights. The thickness of the coating can be estimated using a nomogram of double refraction.

To meet specific tribotechnical problems surface coatings require special properties, e. g. the formation of a friction film to increase wear resistance by implementing the principle of Sharpie. The paper deals with the technological aspects of creating such coatings on iron-containing alloys by combining laser and induction surfacing to obtain a wear-resistant composite coating. Within research, a coating with a composite structure on a substrate of steel 45 with a copper matrix and a reinforcing phase on the basis of Nickel-iron rollers obtained by laser cladding was obtained. The interface between the components of the composite material is studied. The results of studies of the chemical composition and microhardness of the composite coatings are presented. As studies have shown, the use of laser-induction surfacing allows to form a coating of stable quality with minimal consumption of matrix alloy. The proposed technology makes it possible to create a range of different types of composite coatings on iron-containing alloys for different friction velocities and degrees of load by varying the frequency of the reinforcing mesh and the tupe of filler powders.

The influence of working conditions on workers in the foundry production is considered. The results of the analysis of industrial injuries in foundries with different nature of production are given. It is noted that the most of accidents at the place of their incident falls on the fettler-cleaning shops, forming and melting-pouring shops of foundries, and the most traumatic professions are fettler-cleaner, former, furnace-operator, filler and repairman. Analysis of the causes of industrial injuries in foundries showed that about 74% of all industrial injuries occur due to organizational reasons, for technical reasons – about 16%, for sanitary and hygienic reasons – about 7% and for psychophysiological reasons – about 3%.

The working conditions of workers in foundries and their impact on occupational illness are considered. The results of the distribution of occupational diseases in the casting departments and according to professions working in foundries are given. It was found that the working conditions of foundrymen lead to such occupational diseases as silicosis and dust bronchitis, vibration disease and neuritis of the auditory organ. It is noted that about 60% of vibration disease, about 40% of neuritis of the auditory organ, about 80% of silicosis and dust bronchitis from the total number of similar occupational diseases in machine-building enterprises account for workers in foundries.

The results of the study of air quality on workplaces of foundrymen. The results of measures of dust content and content of harmful substances in the workplace areas at foundries with different nature of production are given. It is noted that the dust content in the air of the working area of the foundry areas exceeds the maximum permissible concentrations at all workplaces, with the largest excess noted in the mass production shops. The highest exposures to dust are castings dressers, cleaners and castings technicians. The harmful substances such as carbon monoxide, nitrogen oxides, phenol, formaldehyde, etc. are also were found in the air of the working zones, the content of which is determined by the applied technological processes.