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The development of new medicinal products to treat influenza is motivated by the limitations of existing treatment options, the emergence of drug resistance, and the health consequences of influenza epidemics associated with the highly contagious nature of the virus. Proper planning and implementation of clinical programmes providing reliable data on the efficacy and safety of medicinal products under development requires adherence to recommendations of the regulatory authorities. At the moment, the Russian Federation, the Eurasian Economic Union, and the European Union lack documented recommendations on conducting clinical trials of anti-influenza medicines. There is a need in national guidelines that will reflect the procedure for conducting clinical trials and establish the required amount of data to be submitted with marketing applications for new anti-influenza products. The aim of this study was to analyse possible regulatory approaches to planning clinical development programmes for anti-influenza medicinal products. The article pays particular attention to phase III studies, as the main studies confirming efficacy and safety. The authors described a clinical development strategy and the requirements for the volume and quality of efficacy and safety data. This article is based on the current Russian recommendations for the design and development of medicinal products and guidelines on their evaluation, as well as the recommendations by the U.S. Food and Drug Administration (FDA). The analysis results demonstrate the necessity for elaborating Russian recommendations for clinical studies of medicinal products for the treatment of influenza that will take into account the national legislation and clinical development practices. Such recommendations will streamline the implementation of new effective anti-influenza medicinal products.

The article analyzes the latest changes in legislation and judicial practice of courts of General jurisdiction and arbitration courts with the participation of the head of the organization. Arguments are given in favor of the position on the consideration of labor disputes exclusively by courts of General jurisdiction, arguments are given regarding the need to change the rules of the Code of Arbitration Procedure of the Russian Federation in order to prevent the consideration of labor disputes by arbitration courts.

The relaxation processes that occur near nonmetallic inclusions and take place when thermal and strain stresses appear are discussed. These processes contribute to the formation of local mesoscopic substructures characterized by inhomogeneous dislocation density, plastic rotations, local deformation bands, and slip along inclusion/matrix interfaces. The effect of these processes on the local structural changes in a steel matrix, which determine the role of nonmetallic inclusions and inclusion/matrix interfaces in the formation of a heterogeneous steel structure under various deformation and heat conditions, is shown.

The main factors governing a mixed effect of nonmetallic inclusions as internal sources of microalloying on local strengthening of steels upon laser treatment are systematized and analyzed. The processes, which govern the nature of the microcomposite zone formation, heterogenization regarding the structure of steel matrix and inclusion–matrix phase boundaries, as well as the decrease in the sizes of inclusions and their content in the surface layer, are discussed. The effect of preliminary laser treatment on the mechanism and parameters of crack formation near inclusions upon subsequent deformation at 25–900 and 1000–1250°C is shown. The effect of the saturation zones of steel matrix on the form of crack propagation from inclusions is determined.

Plasticity of heterophase nonmetallic inclusions of various types at hot and cold steel forming was studied. Transformation features of inclusions possessing different phase composition and structure were shown. Inhibiting effect of the second phase of inclusions on the formability of plastic phases at hot and cold strain of the steels was determined. Interaction features of the components of inclusion phases were studied, such as interactions in the inclusion–matrix interfaces and internal phase boundaries in inclusions. Features of the plasticity origin of heterophase inclusions possessing various compositions and structures were discussed.

Transformations of structure associated with relaxation processes in the inclusion-matrix interphase boundaries of 08Yu, 08Kh18N10T, E3 steels and armco-iron under various external impacts are studied. The possibilities of stress relaxation within the inclusion – matrix boundaries as a result of the emission of dislocations or the splitting of these boundaries are shown. The mechanisms of static, dynamic, and electrostimulated splitting, which plays an important role in structural transformations during various steel treatments, are proposed.

Purpose. It is necessary to study the conditions for the initiation of fatigue damages and the weakening effect of corrosion on the corrosion-fatigue wear of railway wheels. The aim of the work was to study the effect of the structure of wheel steel on the development of corrosion processes. Methods. To study the features of the development of corrosion damages in wheel steel the metal of worn wheels (1, 2; samples from the rolling surface, from the inner part of the rim body and from the disk) was used. Accelerated corrosion tests were carried out at room temperature in a special chamber in a humid atmosphere (relative humidity 80...83 %) containing 10 mg/m3 SO2, as well as NO and NO2, which is close to the effect of industrial atmospheres. Metallographic studies were carried out using a Neophot-21 microscope. Results. The features of wheel steel corrosion in different areas of worn out railway wheels are investigated. It is shown that the different corrosion rate of wheel steel is explained by its different structural state (degree of dispersion of pearlite, grain size, nature of the deformed structure). It was found that the rolling surface and the metal of the disc corroded faster than the metal from the center of the rim. Scientific novelty.The features of the mechanism and the rate of development of corrosion of wheel steel in different areas of worn out railway wheels during high-speed tests in an environment close to an industrial atmosphere are established. It is shown that the nature of the microstructure of wheel steel affects the corrosion rate. It is shown that in used wheels the rolling surface corroded faster than the metal from the central part of the rim, which is explained by the effect of stresses created by plastic deformation in a thin surface layer. It was found that the areas of the "white layer" on the rolling surface contribute to the slowdown of corrosion, which is associated with its ultradispersed structure. It was shown that the metal of the disk corroded faster than the metal from the central part of the rim due to the coarser ferrite-pearlite structure of the disk and the presence of ferritic banding.Practical significance.The use of the results obtained will allow developing anti-corrosion measures for railway wheels, which will prevent the formation of various types of defects during their operation.

Purpose . It is necessary to study of the effect of heterophase inclusions on the technological ductility of steels for various purposes. The goal of the work was to study the plasticity level of heterophase inclusions “high-melting phase surrounded with low-melting cover” during the processing of steels by pressure. Methods . Comprehensive methods for the study of heterophase non-metallic inclusions (metallographic, petrographic, X-ray microanalysis methods) were used. Results. It was found that heterophase inclusions “high-melting phase surrounded with low-melting cover” have different structures and phase compositions. The features of the plastic behavior of various phases in inclusions “high-melting phase surrounded with low-melting cover” with various combinations of phases were shown. The interaction of phases in the inclusions during the processing of steel by pressure was analyzed. Scientific novelty. The special features of the plastic behavior of heterophasic ones were identified, including the “high-melting phase, surrounded with low-melting cover” with steel sampling with a vice. It was shown that the process development of interphase rubbing at the boundaries of the included-matrix and at the internal boundaries of the inclusions was shown. The inverse phase inclusion at the third stage of deformation was presented. The possibility of transforming the inclusion of a “high-melting phase, surrounded with low-melting cover” in the process of hot and cold deformation when machining steel with a vice is shown. Practical significance. The results obtained will allow developing technologies for producing steels with regulated content and types of heterophase non-metallic inclusions, which will significantly increase their technological plasticity, as well as prevent the formation of various kinds of defects during the processing of steels by pressure.

In this paper, we study the features of partial dissolution and contact melting of nonmetallic inclusions under conditions of anomalous mass transfer that promotes their fragmentation in the surface layer of hardened steel products. The mechanisms and conditions for laser melting of inclusions, mechanical destruction of solid and liquid inclusions, and the formation of satellite particles are discussed. Inclusion fragmentation upon laser processing is shown to determine the steel hardening level. Based on a study of fast melting and solidification, laser processing changes the structure and properties of nonmetallic inclusions in the surface hardened layers of steel products. The use of the obtained results will allow the development of laser processing modes, thus affecting the size, structure, distribution and content of nonmetallic inclusions in the hardened layers of the products.

Purpose . The goal of this work was to study the localization of deformation near inclusions in steels with various types of metal matrix and the behavior of the inclusions themselves under pulsed loading. Methodology . Dynamic loading of the samples of steels E3 and 08H18N10T was carried out according to the scheme of throwing a thin plate. The calculated pressure was 80...90 GPa, strain rate 100 s -1 , exposure time 1.5 · 10 -6 s. The studies were carried out by several methods: metallographic ("Neophot-21"), electron microscopic (JSM-35). Findings . The features of local changes in the structure of the steel matrix near non-metallic inclusions under pulsed loading were studied. The processes of localization of deformation near inclusions in steels with various types of metal matrix and the behavior of the inclusions themselves under pulsed loading are discussed. The influence of the physical features of high-speed deformation on the formation of the structure of steels and the processes of its localization near inclusions were analyzed. It was established that stresses localized in a steel matrix near the inclusions cause their destruction. Scientific novelty . The analysis of plastic relaxation zones in a steel matrix was carried out, which made it possible to confirm the formation of regions with various orientations, which indicates a shear-rotational reorientation of these stress relaxation zones near inclusions as a result of plastic deformation having a wave nature. The general patterns of structure formation were determined and the influence of the crystal lattice type of the matrix of steels E3 and 08H18N10T on the development of localization of deformation processes near inclusions was shown. Practical relevance . Using the results obtained will allow us to develop pulsed pressure treatment regimes that allow you to influence the formation of the structure near non-metallic inclusions in various steels.

We study the mechanism of dissolution of nonmetallic inclusions under the conditions of high-temperature heating. It is shown that the dispersion of inclusions is associated with several processes (dissociation and partial dissolution of the inclusions, their diffusion fragmentation in the course of selective dissolution and the formation of dispersed “satellite” particles). We also discuss the specific features of the formation of microcomposite zones near inclusions.

Wear particles are formed at the contact surface of railroad wheels close to nonmetallic inclusions and corrosion products, which are associated with structural changes near the contact surface and reaction of the steel with the atmosphere. Such formation of wear particles is analyzed in the present work. The key factors responsible for the formation of the wear particles are identified, and their mutual influence is studied. That permits prediction of the wear at the wheels’ contact surface in different operating position. The wear of the contact surface is shown to be localized at the recess. The wear resistance of the contact surface may be increased by local laser treatment.

The structural transformation of thin-plate pearlite in the cold plastic deformation (drawing) of C86D steel coils with total reduction up to 83.2% is considered. In terms of the physical mesomechanics of structurally heterogeneous media, it is shown that the ferrite–cementite phase boundaries play a significant role in the localization of the deformation and the formation of fragmented mesostructure at different degrees of cold plastic deformation. The transformation of cementite in cold dynamic spheroidization is shown to be associated with the fragmentation of plates and the formation of local submicrocrystalline sections in the pearlite.

Purpose . The problem of the influence of heterophase nonmetallic inclusions on the properties of steels is actual. The goal of the work was to study the main types and structures of heterophase nonmetallic inclusions in steels. Methods . Comprehensive methods for the study of heterophase non-metallic inclusions (metallographic, petrographic, X-ray microanalysis methods) were used. Results. It has been established that heterophase inclusions have different structure and phase composition. The features of various combinations of phases in microcomposite inclusions are shown. The main types of hetero-phase inclusions in steels are established. Scientific novelty. The structural features of heterophase inclusions in steels are established. A classification of microcomposite heterophasic inclusions is proposed: inclusions of the first type “high-melting phase surrounding with low-melting cover”; the inclusion of the second type of “phases are beside”; the inclusion of the third type of “eutectics”; Inclusions of the fourth type “dispersed phases in a non-metallic matrix”; inclusions of the fifth type "eutectics inclusion-matrix". Practical significance. The use of the obtained results will make it possible to develop technologies for the production of steels with regulated content and types of heterophase non-metallic inclusions, which will significantly improve their technological, mechanical and operational properties.

For a coil of rolled C86D steel subjected to accelerated continuous cooling from the hot-deformation temperatures, change in austenite grain size by scores no greater than 1–2 according to State Standard GOST 5639–82 has no significant influence on the impact strength. For C86D steel, the impact strength is directly related to the extent of the ferrite–cementite phase boundaries: the impact strength increases with increase in the boundary length. These results are of practical interest in developing new alloys and conditions of deformation and heat treatment for high-strength pearlitic steels.

Annotation. Formulation of the problem. Since the cooling of rolled metal under deformation-thermal treatment in a real production process occurs not in isothermal condition s, but with a continuous temperature decrease, the study of the decay of austenite under continuous cooling is of great practical importance. Purpose. Investigation of the kinetics of the decay of austenite, as well as the regularities in the formation of the structure of C82DCrV steel during continuous cooling with different rates from an elevated heating temperature. Results. The kinetics of the transformations was studied and a continuous cooling transformation diagram (CCTD) of the decomposition of supercooled austenite of C82DCrV steel (EN ISO 16120-2:2011) alloyed chromium and vanadium from the heating temperature 1040 °C was constructed. When constructing the TCD, the differential thermal analysis method was used, using a reference sample. The most effective intervals of air cooling rates have been established, which make it possible to form at least 90 % of sorbit in the rolled product structure, exclude the release of the excess phase (cementite secondary), and the appearance of structures formed by intermediate and shear mechanisms. The results of the research have been industrialized when developing the cooling mode for wire rod with a diameter of 8.0...12.0 mm from steel C82DCrV on the Stelmor line in the flow of a continuous fine-wire mill 320/150: the temperature of the rolling formation on the Stelmor line must be at least 1040 °C, further accelerated air cooling of the metal turns on the conveyor should be carried out at a rate of not less than 13 °C/sec and not more than 20 °C/sec to a temperature range of 570...540 °C followed by quasi-isothermal exposure under heat-insulating covers.

Purpose of the research . The aim of the work is to identify the effect of laser irradiation on the mechanism and parameters of the formation of microcracks along the inclusion – matrix steel boundaries at different strain rates in the temperature range 25...900 °C. Methodology . Materials for research were industrial steels containing various non-metallic inclusions. Samples of various steels with a pre-polished surface were subjected to laser irradiation at the GOS-30M and KVANT-16 installations, and deformations at the IMASH installation. Results . The influence of the temperature-rate deformation mode at different strain rates in the temperature range 25...900 °C, as well as the laser pulse energy and the duration of the impact on the parameters of nucleation and development of brittle bundles has been established. It is shown that in the temperature range 25...900 °C with different strain rates the higher the temperature of deformation, the greater the magnitude of the critical degree of deformation for all types of inclusions and microdamages. Scientific novelty . The influence of the deformation rate on the value of the critical degree of deformation in the temperature interval of 25...900 °C, upon reaching which micro-destructions occur near the inclusions after preliminary laser treatment, was established. Practical significance . The using of receiving results will allow to elaborate the regimes of laser treatment allowing to use the non-metallic inclusions as inner sources of micro-alloying that will allow to directly influence on the level of crack resistance of steels.

Formulation of the problem . It is of interest to investigate the effect of nonmetallic inclusions and corrosion products of wheel steel on the formation of wear particles on the tread of railway wheels. It is also necessary to identify the specifics of the interaction of wheel steel with the surrounding atmosphere during the operation of railway wheels. The purpose of the article is to study the mechanisms of formation of wear particles on the surface of rolling of railway wheels during operation. Methodology . The effect of inclusions and corrosion products on the mechanism of wear of railway wheels made of R7 steel, which worked for about 5 years under the passenger train, was studied. The wheels were removed from service due to the extreme wear of the rims. We studied the macrostructure and microstructure of wheel steel along the width of the rims. The research was carried out by several methods: metallographic ("Neophot−21"), electron microscopy (JSM−35). Findings . The features of the formation of wear particles near nonmetallic inclusions and corrosion products related to structural changes near the rolling surface of railway wheels as well as to the interaction of steel with the surrounding atmosphere during operation were investigated. The influence of various factors on the role of nonmetallic inclusions and corrosion products in the formation of wear particles is shown, which makes it possible to predict the nature of wear of the rolling surface of railway wheels under various operating conditions. Originality . The main sources and the mutual influence of various factors on the formation of wear particles near nonmetallic inclusions and corrosion products have been established, which makes it possible to predict the nature of wear of the rolling surface of railway wheels under various operating conditions. Practical value . The use of the obtained results will allow to develop methods and regimes of smelting of wheel steel, allowing to influence the size, composition, structure and distribution of non-metallic inclusions, as well as to develop anticorrosion measures in order to improve the reliability and durability of railway wheels.

The solution of nonmetallic inclusions on heating to high temperatures is analyzed. Dispersion of the inclusions is associated with several processes: dissociation and partial solution of inclusions; diffusional disintegration of inclusions in selective solution; and the formation of disperse satellite particles around the initial inclusions.

Purpose . Study of the formation of secondary grain boundaries during crystallization in centrifugally-cast billets (steel grade 40Х25Н20С2). Methodology . The microstructure of hollow billets (steel grade 40Х25Н20С2) produced by horizontal centrifugal casting machines was analyzed. Features of secondary grain boundaries in 40Х25Н20С2 steel were examined in the cast state after annealing at temperatures of 1 100°C and 1 200 °C and equalizing for one and five hours. Metallographic “Neophot−21” and electron microscopics JSM−35, «Tesla», EMW−100B studies were conducted. Findings . It was found that changes in technological parameters of centrifugal casting leading to a reduction of the transcrystallization area and increased surface areas of equiaxed crystals in the structure of centrifugal-cast hollow billets (steel grade 40Х25Н20С2) allow reducing susceptibility to brittle intercrystalline fracture. Hot cracks of crystallization origin and polygonizational cracks form in castings. It is shown that formation of crystallization cracks is significantly affected by chemical heterogeneity, while formation of polygonizational cracks is affected by substructural heterogeneity caused by formation of secondary boundaries. A significant means to reduce susceptibility of cast steel to generation of microfraction is to control the scale and nature of chemical and substructural heterogeneity. Originality . We discuss the main sources of polygonizational formation of secondary grain boundaries in centrifugally-cast steel . Practical value . The obtained results allow using the secondary boundaries to inhibit the development of intergranular cracks.

The development of corrosive damage in bearing steels close to nonmetallic inclusions is analyzed. The influence of the chemical and mineralogical composition of the inclusions on their activity in corrosive media is studied.

The correlation of mechanical hardening to the degree of dispersion of the perlite (interlamellar spacings) and strength indices of rolled steel diameter of 6.5 mm made of steel grade C72D is showed. Using the method of hydrostatic weighing and X-ray analysis it was established that to increase the degree of the deformability of high-carbon rolled during hardware production is the most preferred way is high-temperature unscramble of rolled coils with following process of controlled accelerated air cooling. The results of the research could serve as a basis for the creation of an additional process of assessing the quality of cold wire by non-destructive testing.

Purpose. To determine the universal empirical relationships that allow for operational calculation of scale mass and decarbonized layer depth based on the parameters of the technological process for rolled coil steel production. Methodology. The research is carried out on the industrial batches of the rolled steel of SAE 1006 and SAE 1065 grades. Scale removability was determined in accordance with the procedure of «Bekaert» company by the specifi-cations: GA-03-16, GA-03-18, GS-03-02, GS-06-01. The depth of decarbonized layer was identified in accordance with GOST 1763-68 (M method). Findings . Analysis of experimental data allowed us to determine the rational temperature of coil formation of the investigated steel grades, which provide the best possible removal of scale from the metal surface, a minimal amount of scale, as well as compliance of the metal surface color with the require-ments of European consumers. Originality . The work allowed establishing correlation of the basic quality indicators of the rolled coil high carbon steel (scale mass, depth of decarbonized layer and inter-laminar distance in pearlite) with one of the main parameters (coil formation temperature) of the deformation and heat treatment mode. The re-sulting regression equations, without metallographic analysis, can be used to determine, with a minimum error, the quantitative values of the total scale mass, depth of decarbonized layer and the average inter-lamellar distance in pearlite of the rolled coil high carbon steel. Practical value . Based on the specifications of «Bekaert» company (GA-03-16, GA-03-18, GS-03-02 and GS-06-01) the method of testing descaling by mechanical means from the surface of the rolled coil steel of low- and high-carbon steel grades was developed and approved in the environment of PJSC «ArcelorMittal Kryvyi Rih». The work resulted in development of the rapid method for determination of total and remaining scale mass on the rolled coil steel surface of low- and high-carbon steel grades depending on the temperature coil formation. There was obtained the patent of Ukraine for invention no. 91760 «The method for de termining the total and remaining amount of scale on the rolled steel surface».

The purpose: to increase durability and life of railway wheels and to reduce the cost of purchasing new ones by restoring the mechanical properties of the metal rim and improving its structure. Methods: study using a multiple electron microscope and local X-ray spectral analysis of wheeled steel after induction thermocyclic processing at a high-frequency facility and in a state of delivery. Results: The structure resulting from induction thermocyclic processing - sorbit leads to the formation of compressive stresses, which has a positive effect on the efficiency of the surface of the wheel. As a result, the reliability of the wheel on accidental failures (cranks, chippings, etc.) is improved and, as a result, the safety of the operation of rolling stock is improved. Practical importance: the rational use of induction wheel heating technology will improve the efficiency of the use of rolling stock by significantly reducing the number of purchases of new wheel pairs.

Wind gusts are extreme events which can cause severe damage. Gusts can reach significant values even during medium winds. However, numerical atmospheric models are designed to reproduce average wind speed, not gusts. There are several approaches to estimating wind gusts. Seven different methods are applied to WRF-ARW model output. Results are compared to high-frequency wind speed measurements using ultrasonic anemometers and temperature profiler measurement at the same point in Moscow. Data gathered from synoptic station network over the European part of Russia were also included in the analysis to increase the statistics. None of the wind gust estimation methods shows best results at every skill score. The proposed hybrid method shows good balance between the probability of detection and the false alarm ratio estimates.

The structural behavior of the non-linear optical, nanoporous compound CsLiB6O10 was studied in a wide temperature range. Both the highly anisotropic thermal expansion of the borate with temperature variation and the deterioration of its crystals were investigated. The electron density distribution was analyzed in detail. A reversible, partial transition to a new modification, β-CsLiB6O10, was observed during cooling crystalline and moist samples of CsLiB6O10 to –25 °C. The crystal structure of the new phase is described.

The aim of the work was to study the characteristics of the impact of the dislocation substructure of hot-strain austenite in high-carbon steel and boron microalloying education lamellar pearlite after plastic deformation during continuous cooling. Materials for the study were steel grades 85 and 85R. Methods used: metallographic (optical, electron microscopy – scanning and transmission), X-ray microspectral analysis. Conclusions. Has been further developed model of formation of pearlite in the high carbon steel, which determines the origin of the formation of its lamellar morphology. The role of the dislocation substructure defining character poligonization rearrangements in the cell walls of hot-strain austenite, as well as the interaction of dislocations with interstitial atoms and their complex compounds , which determines the course of the transience of pearlite transformation. The methods of metallographic analysis confirmed the formation of connections BN and atoms of boron influence on the features of structure formation in the steels of pearlite class. The results indicate that the rational choice of the chemical composition of the steel and modes of deformation and heat treatment it is possible to carry out a controlled management of processes of structure formation in rolled steel of high-carbon steels to achieve the required strength class of the metal in a stream of continuous wire mill., Аннотация. Цель работы − изучение особенностей влияния дислокационной субструктуры горячедеформированного аустенита в высокоуглеродистых сталях и микролегирования бором на образование пластинчатого перлита после пластической деформации в процессе непрерывного охлаждения. Материалы для исследований − стали марок 85 и 85Р. Применяемые методы: металлографический (оптическая, электронная микроскопия – растровая и трансмиссионная), микрорентгеноспектральный анализ. Выводы. Получила дальнейшее развитие модель образования перлита в высокоуглеродистых сталях, которая предопределяет генезис формирования его пластинчатой морфологии. Показана роль дислокационной субструктуры, определяющей характер полигонизационных перестроек в стенках ячеек горячедеформированного аустенита, а также взаимодействие дислокаций с атомами внедрения и их комплексными соединениями, что определяет скоротечность протекания перлитного превращения. Методами металлографического анализа подтверждено образование соединения BN и влияние атомов бора на особенности структурообразования в сталях перлитного класса. Полученные результаты свидетельствуют о том, что при рациональном выборе химического состава стали и режимов деформационно-термической обработки представляется возможным осуществлять контролируемое управление процессами структурообразования в бунтовом прокате из высокоуглеродистых сталей для достижения требуемого класса прочности металла в потоке непрерывного проволочного стана., Анотація. Мета роботи − вивчення особливостей впливу дислокаційної субструктури гарячедеформованого аустеніту у високовуглецевих сталях і мікролегування бором на утворення пластинчастого перліту після пластичної деформації в процесі безперервного охолодження. Матеріали для досліджень − сталі марок 85 і 85Р. Методи, які застосовувались: металографічний (оптична, електронна мікроскопія – растрова і трансмісійна), мікрорентгеноспектральний аналіз. Висновки. Отримала подальший розвиток модель утворення перліту у високовуглецевих сталях, яка передбачає генезис формування його пластинчастої морфології. Показано роль дислокаційної субструктури, яка визначає характер полігонізаційних перебудов у стінках комірок гарячедеформованого аустеніту, а також взаємодію дислокацій з атомами впровадження і їх комплексними з’єднаннями, що визначає швидкоплинність перебігу перлітного перетворення. Методами металографічного аналізу підтверджено утворення сполук BN і вплив атомів бору на особливості структуроутворення в сталях перлітного класу. Отримані результати свідчать про те, що за раціонального вибору хімічного складу сталі і режимів деформаційно-термічної обробки можливо здійснювати контрольоване керування процесами структуроутворення в бунтовому прокаті з високовуглецевих сталей для досягнення необхідного класу міцності металу в потоці безперервного дротового стану.

We have studied the mechanism of melting and crystallization of nonmetallic inclusions in contact with steel matrix in the course of laser action. On the example of 08kp, 08Yu, and 60G steels, we have shown that laser action represents a method for local change in the structure of inclusions in surface fused layers as well as in the properties of surface of nonmetallic inclusions.

Changes in “inclusion–matrix” phase boundaries in steel undergoing plastic deformation, which are connected with the susceptibility of nonmetallic inclusions to formation of voids, are studied. Different methods of steel treatment affecting the structure of “inclusion–matrix” interphases are suggested.

We investigated the behavior of nonmetallic inclusions in laser treatment of steels. We established the structural and phase transformations near inclusions, on the inclusion-matrix interfaces, and in inclusions, and the change in the character of microfractures in the vicinity of inclusions under deformation from laser irradiation.

We study the distribution of microinhomogeneous strain in steel near nonmetallic inclusions of various types, which are not susceptible to the formation of hollows. We establish the features of the influence of temperature, plasticity of inclusions, and intersurface stresses on the distribution of microinhomogeneous strain. We study the nature of splashes of microstrains caused by fracture of inclusions and development of sliding along inclusion-matrix interfaces.

We investigated the mechanisms (and conditions) of the formation of plastic cracks (cavities) near non-deformable oxides in steels subjected to various kinds of treatment (plastic deformation, explosive treatment, and laser irradiation) and determined parameters of the formation and evolution of microdefects: critical sizes of inclusions, levels of strain, strain ranges in which fracture processes are controlled by inclusions, and sizes of cavities at various temperatures. We also analyzed the influence of processing conditions (temperature, strain level and rate, loading mode, and the conditions of laser treatment) on the character of interphase cracks on the boundaries of inclusions in steel.