The studies conducted under the conditions of the electric-furnace
melting shop of “EVRAZ ZSMK” have shown that the increase of the duration of the rail steel blowing with an inert gas, when processing
at the aggregate “ladle-furnace” from 63 to 122 min., reduces the number of oxide non-metallic inclusions; while the remaining controlled quality parameters of fi nished rails are not worsen. Production experiments have proved the technical and economic efficiency of silicomanganese of FeMnSi30HP brand instead of silicomanganese of MnS18 brand for deoxidation of rail steel under the conditions of the electric-furnace melting shop of “EVRAZ ZSMK”. An increase in the degree of pass-through assimilation of carbon and silicon has been found (by 4 % and 13 % respectively). The mechanical properties and microstructure of rails, obtained when using experimental techniques, are at the current melting production. According to the obtained calculated data from the use of cost-effectiveness of a new brand of ferroalloy FeMnSi30HP is 13.99-32.64 rubles/t for the rails of different categories.

The paper presents the research of the infl uence of the concentration and composition of nanoscale modifi ers, obtained when using different methods (thermal, plasma-chemical, self-spreading hightemperature synthesis – SHS, mechanochemical and combined with mechano-chemical), on the microstructure and mechanical properties of synthetic grey cast iron in the intraform modifi cation. In addition, in the capacity of nanosized modifi ers dust-like metallurgical waste have been investigated. Classic modifi ers of the Russian production have been used to compare modifying properties. The increase in the Brinell hardness in the range of 13 % has been shown by the samples of cast iron, modifi ed by tungsten and titanium carbides (the SHS method + the mechanochemical one), 10 % – modifi ed by yttrium with zirconium or chromium (the mechanochemical method) and [ά-Fe, TiCx Ny , SiC] (the plasma-chemical method). The increase in the limit of tensile strength by approximately 20 % has been recorded on the samples of cast iron, modifi ed by tungsten and titanium carbides with zirconium (the mechanochemical method). On the samples modifi ed by yttrium with zirconium or chromium (the mechanochemical method) and [α-Fe, TiCx Ny , SiC] (the plasma-chemical method), tensile strength has increased by 8 – 12 %. The concentration of modifi ers, in which the greatest modifying effect has been revealed, has made approximately

0.002 – 0.050 %.

The article describes the technology of 110G13L manganese steel smelting in an electric arc furnace with a capacity of 25 tons by oxidation method. All the major periods of melting have been reviewed, as well as the data on the study of the slag mode in the steelmaking process has been presented. By the calculating method with the use of practical data on the chemical composition of slag oxidation and reduction periods, the estimation of oxygen activity in metal has been carried out. The dependence of oxygen activity in metal on the total content of oxides of manganese and iron in the slag has been shown graphically. In addition, the determination technique of necessary aluminum amount for deoxidation of metal for the purpose of receiving the amounts required in the fi nished metal has been observed. The infl uence of the concentration of aluminum in the metal on impact strength of manganese steel has been studied.

The paper presents the research results of the heterogeneity of hot
plastic deformation of 08Cr21Ni5Ti steel. Extension of samples was
carried out in the vacuum chamber of a testing machine IMASh-20-75 “Ala-Too”. To test the sample it was mounted in the vacuum chamber to the grippers with the help of bars. The junction of platinum – platinum-rhodium couple was welded to the side surface of the sample. The evacuation of air from the chamber was carried out up to a residual pressure of 5·10–5 mm Mercury (6.7·10–3 Pa). Heating of the sample up to 800 – 1200 °C was achieved by the heat from the current of industrial frequency transmitted through it. Accuracy of temperature regulation was ± 5 °C. The deformation of austenitic and ferritic phases was examined in dependence on the total degree of deformation of steel and temperature, the data about the infl uence of these factors on the intensity of slip at the interphase boundaries were also considered. The effect of the temperature on the ratio of hot microhardness of austenite and ferrite in 08Cr21Ni5Ti steel was investigated.

The change of one of the main parameters of wet magnetic concentration – the iron content and magnetic characteristics of products made by the concentration technological scheme of Abagur Enrichment Plant (from classifi er discharge to concentrate of the 2nd stage) has been studied. The iron content in the samples is growing signifi - cantly with the decrease of the particle coarseness. The increment of iron magnetite by the scheme is 27.43 %, the specifi c value of saturation magnetization σs increases by 25.8 A·m2/kg. The growth of specifi c magnetization in the separation fi eld H = 175 kA/m is similar – 25.76 A·m2/kg. The values of specifi c magnetic susceptibility χ in the concentrate are higher in comparison with the discharge. The specifi c product susceptibility decreases in several times with the growth of separation fi eld strength. Throughout the concentration scheme the quantity proportionality of iron content and magnetic parameters of products is observed. Taking into an account all the regularities, magnetic characteristics of the products can be used to control and regulate the process of technological modes of wet magnetic separation processes.

The absence of unambiguous interpretation of experimental data
on the modifi cation of metals and alloys makes it relevant to search and prove hypotheses beyond the classical physical and chemical approach. The paper presents a quantum-mechanical theory of modifying infl uence of substances, in particular the oxides BaO, SrO, CaO in the composition of natural modifi er BSK-2 to metal properties, to complement the classical theory of heterogeneous nucleation of solids. The uniform nature of the modifying infl uence of substances, vibration and ultrasound on the molten metal is connected with the occurrence of the Friedel oscillations. The physics of the contact potential difference shows characteristics of the nucleation process in metal melts. The modifying ability of ultrafi ne inclusions is explained by the theory
of free electrons.

The development of blowing devices with special designs including
vortex lances for maximum spraying of molten slag is the promising
way of increasing the effi ciency of refractory coatings application for converter lining. The numerical simulation of liquid slag crushing has been carried out at different modes of blowing with vortex tuyeres with the use of the main conditions of the mechanics of gas-liquid systems. It has been found out that the particle sizes of the slag carried out of the interaction zone are determined by the gas velocity and gas discharge. The decrease of slag viscosity characteristics helps to reduce the minimum size of the particles. When the slag blowing in the mode of “break”, slag melt foaming is possible, resulting in a decrease in the rate of slag particles and affects adversely the creation of skull on the converter lining.

Interstitial elements in steel, carbon, nitrogen and hydrogen, are
analyzed in terms of their effect on the electron structure, properties
of dislocations, strengthening, plasticity and fracture. It is shown that similarities and differences in the mechanical properties of corresponding solid solutions are controlled by the effect of the above mentioned elements on the density of electron states at the iron Fermi level and, as a result, on the concentration of free electrons. The latter is decreased by the carbon and increased due to nitrogen and hydrogen in the iron, which changes the character of interatomic bonds: carbon enhances their covalent component, whereas nitrogen and hydrogen strengthen the metallic one. The velocity of dislocations in the course of plastic deformation is discussed using the approach of mobile and immobile interstitial atoms. In the fi rst case, they are obstacles for dislocation slip, and mobility of dislocations is determined by the enthalpy of binding between interstitial atoms and dislocations. If interstitial atoms are suffi ciently mobile to accompany dislocations, the character of interatomic bonds within the interstitial clouds around the dislocations is locally changed. As a result, the specifi c energy of dislocations (line tension) and the distance between them in the pile-ups are changed in accordance with the local change of the shear modulus around the dislocations. Based on the performed studies, the effect of interstitial elements on the mechanical properties of steels is discussed. Particularly, the essential similarity between the hydrogen-caused brittleness and the nitrogen-induced ductile-to-brittle transition in the austenitic steels is interpreted.

The protective coating on low-alloy steels Hardox 400 has been welded by electric arc method using the fl ux cored wire SK A 70-G. Such coating works effectively in conditions of strong abrasive wear and shock loads and is used in various industries. Chemical and phase composition and defect substructure condition of the coatings has been investigated using scanning electron microscopy with EDA-technique and x-ray phase analysis. The coatings can be divided in three layers by morphological features. The surface layer with the thickness of 3.5 mm has the property cellular structure crystallization and can be characterized by the presence of faceted particles enriched in niobium. The intermediate layer (0.4 mm) has the structure of an islet type. Transition layer (to 0.02 mm) adjacent to the interface with the substrate, is characterized by columnar and dendritic structure. Heat-affected zone has a total thickness of 4 mm. It has been established that the wear resistance of the coatings is in 2.3 times higher than of the substrate. This is due to the formation of the submicrodimensional structure of crystallization, the release of large amounts of high strength particles of hardening phases and forming a martensitic structure of the α-phase of the coating. The reinforcing phases are Fe3C, the volume fraction of which is 10 %, the carbides of niobium and chromium NbC and Cr3C2 , with total volume fraction of 20 %, and iron boride Fe3B, with volume fraction of 10 %.

The paper presents the results of the analysis of the elemental
and phase composition, defect substructure of the 40Cr steel surface
layer, subjected to alloying by irradiation of fi lm (aluminum or titanium) – substrate (40Cr steel) system by high-intensity pulsed electron beam. It is shown that irradiation of fi lm (titanium) – substrate (40Cr steel) system by pulse electron beam is accompanied by steel alloying to a depth of the molten layer (with the thickness of approximately 15 μm); the formation of polycrystalline (with submicron grain size) of the structure on the basis of α-phase, hardened with nanosized particles of titanium carbide. The irradiation of fi lm (aluminum) – substrate (40Cr steel) system with pulse electron beam leads to the alloying of thin (approximately 2 μm) of the steel surface layer, due to the evaporation of the aluminum from the steel surface; the formation of a martensite structure, hardened by nanosized iron alu-minides.

The comparative layer-by-layer analysis of the structure (along the central axis and fi lleted corner) of bulk and differentially quenched rails at a distance of 0, 2 and 10 mm from the roll surface has been done using the methods of transmission electron microscopy. It has been shown that regardless of the research guidelines and the distance of the researched layer from the roll surface the rail structure of all the categories is represented by the pearlite grains of plate-like morphology, ferrite grains, in the content of which one can observe the particles of cementite of various forms (the grains of ferrite-carbide mixture) and the grains of structurally free ferrite (ferrite grains, which do not contain grain-boundary ferrite in the bulk of the carbide phase particles). The morphology and defect substructure of the revealed phases has been studied, as well as established the localization of stress concentrators. The paper also presents the quantitative dependencies of fragment parameters of the grains of ferrite-carbide rail mixture on the thermal processing mode and the distance from the roll surface.

The melt temperatures and the maintenance of elements (C, Si,
Mn, S, P) are given in various levels of a blast furnace. Uniqueness of this experiment is that, unlike laboratory installations, the real conditions of a blast furnace created ideal thermal insulation of liquid melt on all directions and thermal diffusions of elements (C, Si, Mn, S, P) in the vertical direction. From these experimental data the authors have calculated thermodiffusion heat of cast iron melt elements and have shown that carbon, silicon, manganese and phosphorus, both in the liquid and solid metal, move towards the hotter parts of the system, and sulfur, conversely, towards the colder. This conclusion can 
be used at the description of existing and creation of new processes of metal desulfuration.