The aim of this work is the experimental study of the feasibility and advisability of reducing processing of steel slags in order to obtain the metal and oxide phases, which can be used in the metallurgical industry and in the industry of structural materials. The slag from slag dumps of Zlatoust Metallurgical Works (the Russian Federation) has become the object of the experimental study. These studies have included some experiments on the recovery of slag samples with carbon. The composition of the experimental samples was determined by electron microscope analysis. The carried out theoretical and experimental studies suggested that the mass of the metallic phase obtained during recovering can be up to 20 % by weight of the initial slag and even slightly higher. At the same time, the iron, which is contained in slag, can be recovered almost completely. Besides, some prevailing or significant part of such elements as chrome, nickel, manganese, and some other valuable components can transmit into the composition of metal. It is expedient to carry out the liquid-phase recovery of slag at temperatures about 1500°С or higher to obtain more complete recovery of metals and formation of the consolidated metal phase. This study shows the expediency of the prior solid-phase reduction of the slag at temperatures of 1100 - 1200°C. This process will enable the most part of the iron included in slag as oxides to convert them into the form, which will be susceptible to magnetic separation. The subsequent magnetic separation enables to separate the fraction with a high content of valuable metals from the oxide fraction depleted by valuable metals; this fraction can be used for production of building materials. When designing units for implementation of the developed technology, it is recommended to provide some measures for the utilization of large volumes of carbon monoxide and vapors of the metals presented in the gas phase. The use of the received gas as a reducing agent for preliminary solid-phase slag recovery can become the way of CO utilization. The research allowed developing the scheme of deep processing of slag dumps of this kind.

The paper presents a mathematical model of decarburization process with continuous supply of pellets and using fuel-oxygen burners subject to changes of slag oxidation and oxygen distribution on the of melt components oxidation during the melting. The algorithm and program of the proposed model can be used to calculate the controlled oxidative refining at electric melting of metalized pellets in an arc furnace bath. The article considers calculated by the model curves of the process components of metal decarburization, slag oxidation and the rate of steel heating from decarburization during the period of steel melting to achievement of the final metal weight in the bath of 150-t EAF at different consumption of pellets and constant supply of oxygen by fuel-oxygen burners at the melting. The data confirm the decisive contribution of oxygen from fuel-oxygen burners in the melt decarburization. General view of the curves of changes of the decarburization process components coincides with the literature and experimental data. This makes it possible to exercise effective control of electric parameters of electric melting (with electrodes current, voltage steps, etc.), providing maximum radiation of electric arcs on the surface of metal and slag. Thus, the oxygen flow through the fuel-oxygen burner allows to realize technical solutions for the electric melting of pellets in high temperature zone of the furnace. The flow of pellets, granular materials and gas mixtures are concentrated in the influence zone of electric arcs on the surface of the melt, where the processes of heating and melting of pellets are made with higher speeds than all the blown methods of loading of metalized pellets into the unit, allowing you to achieve higher technical, economic and energy-technological parameters of metallized pellets melting.

The results analysis of numerical and experimental studies on edge bending at the 1420 line was performed. It determined the influence of about-edge zone of the billet on the quality of finished welded pipe. It was found that the geometry of the billet's edges effects further on the billet's parameters on preform zone of molding presses, assembly and welding mill and mechanical expander. The contact and non-contact areas of about-edge zone of the billet and the tool of edge bending press were determined. It was revealed that the deviation in the edge geometry effects further also on the quality of weld joint geometry and about-edge zone after welding and assemblage. These deviations later lead to such defects in the about-edge zone like longitudinal edges of mixing and deviation from the theoretical circle. A number of mathematical and experimental studies was performed on the geometric parameters of billets at edge-bending and it was stated that the about-edge zone of pipe billet under loading has form of the deforming tool, as pipe billet at loading covers it. Deforming tool of the edge-bending press has involute profile, i.e., bent part of the edge in the contact area should have involute profile during loading. To identify the nature of the distribution of pipe billet curvature the authors have investigated the pipe billets deformation using modem computer systems at the area of edge-bending. The results of the studies have shown: the contact area of the deforming tool and pipe billet, coordinates of the loop across the pipe billet width. Contact area the billet and deforming tool is about-edge zone of pipe billet which is in contacts with the lower deforming tool - the die and the upper deforming tool - the punch. According to the research it was found that the about-edge zone of the pipe billet does not completely cover the upper deforming tool and has both contact and non-contact portions, therefore, the curvature distribution pattern of the billet edge and the punch profile differ, and blown calculation methods need to be improved. The main parameters of billets at edge-bending were determined. A comparative analysis of the measurements results of edge geometry was made using experimental and computational methods.

 The article describes the analysis of degassing technology of 09G2S steel, smelted in an electric arc furnace and processed in the ladle furnace in the conditions of EAF JSC “Ural Steel”. The main parameters of steel degassing have been identified. These parameters, determining the hydrogen removal efficiency on the degassing unit of chamber type, are: level and period of steel degassing, argon consumption, metal temperature, thickness of the slag layer and the value of free board. It was found that the most significant impact on the hydrogen content can be observed at increasing the duration of deep steel degassing up to 20 minutes. Further increase in treatment time is not advisable. The greatest effect of the residual pressure during degassing was observed while reducing the minimum pressure to 2 mbar. The results of steel degassing worsen significantly at the increasing of the residual pressure. Increasing metal temperature up to 1600 - 1620°C promotes the removal of hydrogen, but at temperatures above 1620°C substantially slows the hydrogen removal. The quantitative impact of steel degassing parameters and the regression equation were found and that allows to predict the results of the hydrogen removal. This equation allows to determine the steel degassing parameters and to achieve a predetermined content of hydrogen in steel. The rational parameters of steel degassing were determined, which provide of hydrogen content to 2.1 ppm in the steel: a superheat temperature of metal - 100-110°C, the duration of the steel degassing process to 20 minutes under the pressure in the vacuum vessel at most 1.5 mbar, argon consumption - 0.05 m³/t. The losses of metal temperature are determined by the total duration of the processing, which depends on the duration of deep vacuum, on the technical capabilities of equipment and organization of the degassing steel process. The minimum residual content of hydrogen in steel, which is 1.6 ppm, is ensured at carrying out of steel degassing with superheat temperature of 120 - 125°C for 40 minutes at a pressure in the vacuum vessel at most 1 mbar and with the consumption of argon – to 0.072 m³/t.

In this paper have been identified the main parameters of steel degassing. They determine hydrogen removal efficiency by ladle degassing plant, operating in EAF JSC "Ural Steel": vacuum level, vacuum period, argon consumption, ladle temperature, the thickness of slag layer and freeboard.

The quantitative effect of the vacuum parameters was determined. The regression equation that allows to predict the results of the removal of hydrogen was obtained. This equation can choice value of vacuum parameters in order to achieve a specified of hydrogen content in the steel.

The rational vacuum parameters have been defined which provide of hydrogen content of 2.1 ppm in the steel: a metal superheat temperature 100-110 °C, vacuum period to 20 minutes under pressure in the vacuum vessel at most 1.5 mbar, argon consumption - 0.05 m³/t.

The method of determining the surface stress by X-ray method (by an example of steel samples of critical parts of railway transport) was examined taking into account the special surface preparation at the point of measurement. The features of the measurement surface stress by X-ray method were considered; the applicability of the designed layout of the portable X-ray diffractometer was shown. The diffractometer operates as follows. Changing the angle of diffraction in the presence of mechanical stresses leads to a shift of the diffraction peak on the recorded diffraction spectrum according to the peak position in the absence of stresses. The detector records the diffracted X-rays and passes the discrete information about the distribution of radiation intensity (which is captured by the detector) to the personal computer using an analog-digital converter. A special program “STRESSCONTROL” was developed for computer processing of the recorded diffraction spectra. The program allows to display graphically the diffraction spectra recorded by the detector, to control of diffractometer operation and to calculate the stresses using databases on metals and phases. Computer processing of the diffraction profiles is used to identify the position of the gravity center. The algorithm of the program involves the separation of the background, approximation of the data array to a curve and exact definition of the gravity center of the smoothed profile. The surface stresses on the fragment of the solebar of 20GL-type steel (after normalization and volume-surface hardening), cut from the box opening area with R55-radius, were measured. The surface stresses definitions for normalized fragment showed the results close to zero and the results of surface stresses definitions for the fragment with a volume-surface hardening showed a significant compressive stresses. Thus, the shape of the diffraction peak and the level of surface stress are directly related to the investigated steel microstructure features. In this case, the X-ray method of determining the surface tension may be an indicator of the surface state.

The method of determining the surface stress by X-ray method (by an example of steel samples of critical parts of railway transport) was examined taking into account the special surface preparation at the point of measurement. The features of the measurement surface stress by X-ray method were considered; the applicability of the designed layout of the portable X-ray diffractometer was shown. The diffractometer operates as follows. Changing the angle of diffraction in the presence of mechanical stresses leads to a shift of the diffraction peak on the recorded diffraction spectrum according to the peak position in the absence of stresses. The detector records the diffracted X-rays and passes the discrete information about the distribution of radiation intensity (which is captured by the detector) to the personal computer using an analog-digital converter. A special program “STRESSCONTROL” was developed for computer processing of the recorded diffraction spectra. The program allows to display graphically the diffraction spectra recorded by the detector, to control of diffractometer operation and to calculate the stresses using databases on metals and phases. Computer processing of the diffraction profiles is used to identify the position of the gravity center. The algorithm of the program involves the separation of the background, approximation of the data array to a curve and exact definition of the gravity center of the smoothed profile. The surface stresses on the fragment of the solebar of 20GL-type steel (after normalization and volume-surface hardening), cut from the box opening area with R55-radius, were measured. The surface stresses definitions for normalized fragment showed the results close to zero and the results of surface stresses definitions for the fragment with a volume-surface hardening showed a significant compressive stresses. Thus, the shape of the diffraction peak and the level of surface stress are directly related to the investigated steel microstructure features. In this case, the X-ray method of determining the surface tension may be an indicator of the surface state.

Structure formation staging of a single crystal (110) [001] of the alloy with Fe-3 % Si bcc was investigated directly in deformation zone during cold rolling. Laboratory rolling mill was abruptly stopped during the rolling of every sample to create a visible «deformation zone». Lubrication was used on some samples to reduce the friction coefficient. Deformation structure was investigated by the methods of metallography and orientation electron microscopy. The connection of the experimental data with the calculated stress state was analyzed in Deform-3D program for different values of cold rolling friction coefficient. It was demonstrated that stress state in relation to friction coefficient can considerably influence the generation of mesostructure and crystal texture evolution in the material. It was observed that deformation bands formed in a cold rolled single crystal that was subject to high friction and relatively low strain value. Orientation analysis of the deformation bands linkage demonstrated in this area the existence of alternating microbands with slightly different orientations, separated from each other by low-angle boundaries. In case of single crystal (110)[001] rolling with lubrication (low friction) twinning was noted even for low strain level. As it seems, the reduction of surface energy input into the total energy of twin formation was the result of twinning. It was demonstrated that during all deformation process twins of both systems either preserved a strong L3 crystallographic connection with the matrix or L3 disorientation transformed into close special disorientations Y.llb and L43c in connection to local reorientation of crystal lattice. Based on experimental data dislocation model of deformation mesostructure formation during single crystal (110)[001] cold rolling has been proposed. This model deals with microbands formation at the initial stage of deformation bands appearance, the formation of transition bands parallel to rolling plane which retain initial orientations in dynamics, formation of transition bands tilted to the rolling plane with the habit planes parallel to {112} matrix planes. These transition bands are equivalent to shear bands the habit of which makes the angle of about 17° with the rolling plane.

Deformation resistance characteristics of nitrogen-bearing steel of Cr-Ni-Mn alloying composition have been defined with the help of universal research complex Gleeble 3800 at various temperatures between 1200 and 800 ^:C depending on the strain rate. Temperature and deformation conditions of dynamic recrystallization depending on the strain rate have been determined by analyzing the deformation diagrams, namely that of the deformation limit beginning the process. Optimum temperature regimes for industrial hot stamping, forging and rolling have been recommended. It has been found that at a degree of true strain e = 0.9 the dynamic recrystallization of steel occurs in the range of 10~² + 2 s^_1 of strain rate at temperatures not lower than 900°C. The experimental data have been confirmed by metallographic research. Studies have shown that the processes of structure formation during isothermal deformation of steel at different speeds have some differences at temperatures above 900°C. The higher the temperature and the lesser the strain rate, the greater is the development of relaxation. It was found that at a strain rate of 0.01 s^_1 corresponding to hot stamping, dynamic recrystallization in the temperature range of 1200 - 1100°C deformation starts at values equal to e = 0.1 (about 10 % of relative reduction). When the temperature lowers to 1000 and 900°C it is necessary to accumulate deformation to 20 and 30 %, respectively. Increasing the strain rate to 0.1 s^_1 (when forging) leads to the fact that at temperatures above 1100°^:C dynamic recrystallization begins at a degree of deformation about 20 %; at temperatures of 1000 and 900°C about 28 and 35 %, respectively. When the strain rate is  1-2 s^_1 (when rolling) dynamic recrystallization starts when the temperature range is 1100 -1000°C and degree of deformation equals to 30 %. Lowering the temperature to900°C, as well as increasing to1200°C, increases the limit degree to 36 %.

Methods of increase in firmness and uniformity of the structure of cast blanks of responsible appointment from high-strength alloyed steels are briefly considered. It is shown that only alloying not always provides necessary mechanical and office properties of the responsible products received by casting. It is noted that the most widespread mode of casting in sandy forms doesn't allow to effect on hardening and consequently on the structure and properties of cast metal and characteristic hardly removable defects, arising at the same time. The critical technological parameters of casting are specified to thin-walled forms: thickness of a facing layer and the metal equipment, metal supply mode, technological parameters of the filled-in metal, mode of creation of the directed casting hardening, and also quantity and material of microrefrigerators. The researched results of influence of ladle impact on the hardening metal of heavy case castings of special steel are given. Quality of metal of the castings received by the following options is analyzed: suspension priming of liquid metal in a metalshell form with compulsory cooling (complex influence), in a metalshell form with compulsory cooling (external influence), in a volume sandy form. Probe of a macro structure showed that the largest grain turns out in a volume sandy form; in the central area of casting the shrinkable porosity is observed. Increase in speed of crystallization and hardening of casting leads to structure crushing and increase in firmness of metal along the height and section of casting. Conditions of hardening influence also on morphology of nonmetallic inclusions and on the nature of dendrite structure. Noted advantages are especially noticeable at complex impact on the hardening casting. At the same time there is sharper drop of overheat temperature at the input of microrefrigerators and compulsory cooling of a thin-walled form and increase in the centers of crystallization and in effect of suspension supply at closing stage of hardening. Mechanical properties of the steel castings, received with complex influence, especially impact strength and plasticity, are much higher than at the casting received in a volume sandy form. Increase in mechanical properties is explained by the accelerated heat sink, structure crushing and increase in firmness of casting metal and more favorable distribution of nonmetallic inclusions. Not less important advantages of the developed technology are increase in metal yield through the metal consumption, increase in surface smoothness of casting and a possibility of reference of this mode in the low-waste and resource-saving category.

Thermodynamic analysis of oxygen solutions in titanium- containing Fe-Co melts was carried out. The equilibrium constants of interaction of titanium and oxygen dissolved in the Fe-Co melts, the activity coefficients of titanium and oxygen at infinite dilution, and the interaction parameters characterizing these solutions for melts of different composition at 1873 К were determined for the first time. As the cobalt content in the melt grows the equilibrium constants of interaction of titanium and oxygen are decreased from iron (lgK(FeO·TiO₂) = -7,194; lgK(TiO₂) = -6,125; lgK (Ti₃O₅) = -16,793; lgK (Ti₂O₃) = -10.224) to cobalt (lgK (CoO· TiO₂) = -8.580; lgK (TiO₂) = -7.625; lgK (Ti₃O₅) = -20.073; lgK (Ti₂O₃) = -12.005). Titanium contents in equilibrium points of oxide phases (Fe, Со) О· TiO₂. TiO₂, Ti₃O₅ and Ti₂O₃., were determined. The titanium content in equilibrium point (Fe. Со)О · TiO₂ ↔TiO₂ decreases from 1,0· 10^-4 % Тi в in the iron to 1,9-10^-6 % Ti in cobalt. The titanium content in equilibrium point TiO₂ ↔ Ti₃O₅ increases from 0.0011 % Ti in the iron to 0.0095 % Ti in cobalt. The titanium content in equilibrium point Ti₃O₅ ↔ Ti₂O₃, increases from 0.181 % Ti in the iron to 1.570 % Ti in cobalt. The dependences of the oxygen solubility on the contents of cobalt and titanium in the studied melts were calculated. With increasing cobalt content in melt to 20 %, the deoxidation ability of titanium decreases and then rises with the further addition of cobalt. In iron. Fe-20 % Co and Fe-40 % Co alloys deoxidation ability of titanium is practically the same. The curves of the oxygen solubility in titanium-containing iron-cobalt melts pass through a minimum, which shifts toward lower titanium contents with increasing cobalt content of the melt. Further titanium additions leads to an increase in the oxygen concentration in the melt so that with the higher cobalt content in the melt, the increase in the oxygen content after the minimum is steeper as titanium is added to the melt.

To identify associates in a binary metal solution with positive deviations from Raoult's law, a version of ideal associated solution model was used that only took into account self-association of one solution component. Besides, absolute (rather than relative) characteristics of mass were used to identify chemical equilibrium of components according to the law of mass action. As a result, this allowed finding the chemical equilibrium constants between solution associates and monomers, which have a clear physical meaning, rather than empirical constants of associates' complex formation. This technique, however, required introduction of an additional calculated characteristic - the sum of all chemical compounds in the solution. It was found that this value was numerically equal to the reverse activity coefficient of the solution's non-associated component. The possibility of independent determination of such characteristic allowed notable simplifying the initial system of computational equations, i.e. excluding the equation of solution's molar composition normalization, only keeping two equations of material balance of solution components. The resulting algorithm allowed using the numerical method to solve both the "inverse' problem (finding the degree and thermodynamic properties of the self-associate based on testing data) and the "direct' problem (finding solution component activities according to their thermodynamic properties). At the present time, there is almost no reference information about thermodynamic properties of self-associates; therefore, the solution of the direct problem currently will only be useful for the verification of the inverse problem solution results. Associates were identified for 11 binary alloys containing chromium or copper, i.e. chemical elements mostly amenable to self-association. It was found that each of the mentioned elements could form associates of different degrees, from 3 to 16. For alloys that form associates with low degrees (less than 10), the calculated energy of associate formation necessary for one chemical bond was found to be about 15 kJ/mole. The full calculated energy of associate formation for alloys with high degree of associates (more than 10) was found to be about 360 kJ/mole. It was noted that concentration dependence of the association degree was not quite stable and tended to increase at low concentrations of the associated component. Under the employed calculating model, however, the absolute error of activity isotherm approximation of tire analyzed alloys remained low and ranged 0.004 - 0.025.

Texture of low carbon microalloyed steel sheets with bainitic microstructure produced by TMCP (thermo-mechanical controlled processing) was investigated using EBSD (electron backscatter diffraction) technique. Samples with high and low penchant for fission formation (secondary cracks at the fracture surface) were investigated. Formation of fission relates with the elongated areas of grades which have uniform orientation (001)[110]. Probably the formation of these areas is a result of features of g→α transformation at different parameters of TMCP.

The experimental data on the end thickness variation of tubes produced by PRP-80 of “Sinarsky Pipe Plant” was analyzed. The data of length of thickened ends of rough and finished tubes are shown. The configuration of thickened ends was displayed as conical shape with rectilinear generators, and the linear regression equations were obtained. The formula for calculating of the length of front and back thickened ends was also determined. The data of thickness variation of rough and finished tubes are shown.