Showing papers in "Steel in Translation in 2012"
TL;DR: In this paper, the microstructure of a broad range of low-carbon low-alloy high-strength pipe steels produced by thermomechanical treatment is studied by transmission electron microscopy.
Abstract: The microstructure of a broad range of low-carbon low-alloy high-strength pipe steels produced by thermomechanical treatment is studied by transmission electron microscopy Such steels consist of a mixture of various types of ferrite matrix with high-carbon phases and structural components The classification of the structures is refined, with separate consideration of the components forming the low-carbon ferrite matrix and the high-carbon components that appear as isolated regions and also as layers and inclusions in bainitic ferrite A deformational dilatometer is used to determine the temperatures ranges in which the various phases and structural components are formed
24 citations
16 citations
TL;DR: In this paper, the behavior of nonmetallic oxide inclusions and oxygen in the vacuum-jet refining of steel is investigated, and the behavior is shown to be similar to ours.
Abstract: The behavior of nonmetallic oxide inclusions and oxygen in the vacuum-jet refining of steel is investigated.
15 citations
14 citations
TL;DR: In this article, the formation of microstructure and substructures in the rims of railroad wheel pairs by plasma treatment is investigated, and it is shown that the hardening of the surface layer in plasma quenching is largely due to formation of nonequilibrium metastable structure that is practically amorphous in the surface zone.
Abstract: The formation of microstructure and substructures in the rims of railroad wheel pairs by plasma treatment is investigated. The hardening of the surface layer in plasma quenching is largely due to the formation of nonequilibrium metastable structure that is practically amorphous in the surface zone. This structure is transformed to a narrow zone of complete and incomplete quenching, with a nonuniform martensite + troostite structure.
10 citations
TL;DR: In this paper, the Bauschinger effect on microalloyed pipe steel was investigated with one and several extension compressive cycles on a Gleeble-3800 system, at room temperature and elevated temperatures.
Abstract: The Bauschinger effect is investigated on samples of microalloyed pipe steel. Tests are conducted with one and several extension-compression cycles on a Gleeble-3800 system, at room temperature and elevated temperatures. The influence of temperature on the final sheet properties is considered in conditions of small alternating deformation, so as to simulate the straightening of hot-rolled sheet. The successive influence of each cycle on the final properties of the metal is demonstrated. The strength of the final strip may be modified by 150 MPa, depending on the selected straightening temperature.
10 citations
8 citations
8 citations
TL;DR: In this article, a new method has been developed for more intense spheroidization of cementite, which employs preliminary conversion of the steel to bainite structure, by means of an internal heat source, so as to ensure the Geveling effect.
Abstract: A new method has been developed for more intense spheroidization of cementite. The method employs preliminary conversion of the steel to bainite structure. Spheroidization is produced by nonisothermal holding at high temperatures, by means of an internal heat source, so as to ensure the Geveling effect. This method may be used in production lines.
8 citations
TL;DR: In this article, the physicochemical interpretation of the equilibrium parameters for iron ore reduction in a humid atmosphere, for the systems of H2-H2O and CO-CO2, is presented.
Abstract: 103 The reduction of metal oxides by gaseous and solid agents is fundamental to metallurgical technologies. In view of its importance, the existing theoretical and applied research must be periodically reviewed and sometimes corrected. Thermodynamic analysis of the reduction of iron oxides in binary gases H2–H2O and CO–CO2 permits very precise determination of the parameters of equi librium states for individual reduction reactions [1]. However, practically all reduction processes involve complex gas mixtures [2] and multicomponent con densed phases. In that case, thermodynamic analysis is complicated by the dozens of reactions that occur. The parameters of such equilibria are listed in huge tables, while the literature lacks relevant graphs, although three dimensional diagrams and their iso thermal cross sections would often be useful. In the present work, we propose a systematic approach to the physicochemical interpretation of the equilibrium parameters for iron ore reduction in a humid atmosphere, for the systems
7 citations
TL;DR: In this article, the distribution of chemical elements over the area of the corresponding metallographic image is shown for the example of copper, which is extremely nonuniformly distributed, even within a single grain.
Abstract: Mathematical analysis permits quantitative and qualitative assessment of the phase composition of alloys. The distribution of chemical elements over the area of the corresponding metallographic image is shown for the example of copper, which is extremely nonuniformly distributed, even within a single grain. The correlation between the colors of the pixels in the image is assessed by constructing multiple-regression models. On that basis, precise conclusions may be stated regarding the phase combinations and their dispersity in the cast state and after heat treatment.
TL;DR: In this article, phase composition and microstructure of the scale on P6M5Φ3 and P12M3K5 Φ2 steel are studied by X-ray microanalysis.
Abstract: The phase composition and microstructure of the scale on P6M5Φ3 and P12M3K5Φ2 Steel are studied by X-ray microanalysis. The results are used to improve the utilization of refractory elements from the metal-oxide wastes of high-speed steel.
TL;DR: In this article, a thermodynamic analysis of the reaction between manganese and nickel oxides (individually and in a mixture) and chloride solutions was performed in laboratory conditions.
Abstract: oped in (3-5). That permits the production of high� quality manganese concentrates from ore and ferro� manganese concretions of different composition, as well as slag and dust from manganesealloy produc� tion. In the concentrate, 93-94% of the manganese is extracted. The concentrate contains 59-64% Mn, 0.02-0.50% Fe2O3, 0.5-1.0% SiO2, 0.004-0.009% P, traces of S, 3-4% CaO, and 3-5% CaCl2. We know that ferromanganese concretions in the Pacific Ocean and the Gulf of Finland contain nickel (around 0.5%), cobalt (up to 0.27%), and other nonfer� rous impurities. In calciumchloride enrichment, these metals remain in the tailings, whereas nickel is an impor� tant alloying element. At the boundary of the Kemerovo region and the Altai region, deposits of manganese ore containing nonferrous impurities have been found. Table 1 presents the chemical composition of these ores (5). It follows from Table 1 that Sugul ore is lean, since the Mn content is no more than 20%. The Chumai ore has a relatively high Mn content but the phosphorus concentration is relatively high. Therefore, such ore, like ferromanganese concretions, cannot be used for the production of standard manganese alloys without preliminary enrichment. The present work is devoted to the thermodynamic analysis of the reaction between manganese and nickel oxides (individually and in a mixture) and chloride solutions. The same reaction is also investigated in laboratory conditions. For the leaching reactions
TL;DR: Theoretical and experimental results, as well as experience in the production of thin steel sheet at various enterprises, reveal the aspects of cold rolling and trimming that affect the surface quality of the final strip.
Abstract: Theoretical and experimental results, as well as experience in the production of thin steel sheet at various enterprises, reveal the aspects of cold rolling and trimming that affect the surface quality of the final strip. Means of meeting the current requirement on the surface roughness of thin steel sheet are discussed.
TL;DR: In this article, a production technology for K60 steel strip suited to the production of gas-line pipe (diameter 1420 mm; wall thickness 26.4 mm) has been developed, along with the corresponding chemical composition of the steel.
Abstract: A production technology for K60 steel strip suited to the production of gas-line pipe (diameter 1420 mm; wall thickness 26.4 mm) has been developed, along with the corresponding chemical composition of the steel. By improved cold working of nonrecrystallizing austenite and its retention until the onset of accelerated cooling, the grain size and the grain-size fluctuation of the final ferrite-bainite microstructure of the steel strip may be reduced, so as to ensure good DWTT data. The proposed technology has been tested industrially on the 5000 mill at OAO Magnitogorskii Metallurgicheskii Kombinat.
TL;DR: In this article, a dynamic model of the furnace processes during the combustion of coal-water fuel is presented, where the authors make the following approximations regarding the furnace chamber and combustion process.
Abstract: Coal is an important and inexpensive fuel used in industrial heat generators of various types and in heat� ing residential and public buildings. Customer requirements on coal quality are met by enrichment, which gives rise to finely disperse tailings. The best means of disposing of enrichment wastes is their combustion in water–coal suspensions [1]. In that case, all the coal is used directly in combustion, and the ash formed may be used in construction. A promising approach is the combustion of coal–water fuel in turbulent furnaces. In constructing a dynamic model of the furnace processes during the combustion of coal–water fuel, we make the following approximations regarding the furnace chamber and combustion process. Two sepa� rate fluxes enter the furnace: suspended coal fuel (con� sisting of the organic component, ash, moisture, and volatile components); and air. Consequently, the het� erogeneous mixture within the furnace consists of two phases: a condensed phase and a gas phase.
TL;DR: In this paper, the basic factors responsible for the steel's performance and their optimal values are identified and analyzed. But, they do not consider the effect of the type of steel used for constructing the pipeline.
Abstract: 687 Large diameter welded pipe of strength category K65 (X80), which is manufactured by numerous Rus sian and foreign companies, is used for the construc tion of gas pipelines [1, 2]. All such high strength pipe conforms to the relevant Gazprom requirements but will differ in chemical and phase composition, struc ture, and correspondingly mechanical properties. Hence, we need to identify the basic factors responsi ble for the steel’s performance and to determine their optimal values.
TL;DR: In this article, the coke consumption as function of coke-nut consumption and coke wear M10 was investigated in a blast furnaces with different cokenut consumption, with the goal of assessing the effectiveness of COKE nuts in blast-furnace smelting.
Abstract: The operation of blast furnaces with different coke-nut consumption and coke quality is investigated, with the goal of assessing the effectiveness of coke nuts in blast-furnace smelting. The coke consumption is investigated as function of the coke-nut consumption and the coke wear M10. Uniform blast-furnace operation is possible when the coke-nut consumption is no more than 20 kg/t, with satisfactory coke quality (M10 must be no more than 9.0%). The mean the mean rate of replacement of coke by coke nuts is 0.67 kg/kg of nuts.
TL;DR: In this paper, the magnetic properties of amorphous metal alloys based on iron, silicon, and boron, with additions of other elements, were investigated at liquid-nitrogen temperatures.
Abstract: The magnetic properties of amorphous metal alloys based on iron, silicon, and boron, with additions of other elements, are investigated at liquid-nitrogen temperatures. The magnetization and saturation magnetic field (magnetic hardness) of the alloy depend on the element added (carbon, phosphorus, or nickel). The maximum saturation magnetization is observed for the alloy with carbon, and the maximum saturation magnetic field for the alloy with phosphorus.
TL;DR: In this article, the thermal and mechanical treatment of high-carbon steel rebar is considered in laboratory tests and computer simulation, and the dependence of the mechanical properties on the temperature and the tensile forces in thermal treatment is established.
Abstract: The thermal and mechanical treatment of high-carbon steel rebar is considered in laboratory tests and computer simulation. The dependence of the mechanical properties on the temperature and the tensile forces in thermal and mechanical treatment is established. Certain treatment conditions are shown to increase the strength and plasticity of the steel.
TL;DR: By combined study of heat-transfer and reduction processes, the factors that determine the blastfurnace reduction of titanium oxides are analyzed in this paper, where the authors proposed a combined heat transfer and reduction process.
Abstract: By combined study of heat-transfer and reduction processes, the factors that determine the blastfurnace reduction of titanium oxides are analyzed.
TL;DR: In this paper, a criterion for front linearity of the sheet is developed and the basic parameters affecting sheet flexure are the temperature gradient over the slab cross section and the insertion angle of sheet in the rollers.
Abstract: In thick-sheet rolling, formulas are obtained for the kinematic parameters of the deformation source, the torques, and the front flexure of the sheet leaving the rollers. A criterion for front linearity of the sheet is developed. The basic parameters affecting sheet flexure are the temperature gradient over the slab cross section and the insertion angle of the sheet in the rollers.
TL;DR: In this article, the geometric and temperature conditions of pipe blanks of strength classes K60 and X80 are formulated, so as to ensure the required structural state and specified mechanical properties of the blank.
Abstract: Models are developed to describe and predict the geometric and temperature conditions of thick-sheet rolling at different stages (with determination of the billet parameters, its chemical composition, and also the conditions of heating, rough and final rolling, and accelerated cooling). On that basis, effective production conditions for pipe blanks of strength classes K60 and X80 are formulated, so as to ensure the required structural state and specified mechanical properties of the blank.
TL;DR: The Bovanenkovo-Ukhta gas pipeline employs large diameter welded steel pipe of strength class K65 (X80), produced by various Russian and non Russian companies as mentioned in this paper.
Abstract: 14 The construction of the Bovanenkovo–Ukhta gas pipeline employs large diameter welded steel pipe of strength class K65 (X80), produced by various Russian and non Russian companies [1, 2]. All the pipe meets the requirements of OAO Gazprom but there are some differences in its mechanical properties—most nota bly the crack resistance—on account of differences in the chemical composition (within the API require ments) and the sheet production technology (con trolled rolling and subsequent accelerated cooling).
TL;DR: In this article, the front curvature of the sheet leaving the rollers is identified and a means of compensating the sheet flexure at the roller exit is proposed to determine the rolling parameters responsible for asymmetry of the process in the vertical plane.
Abstract: Laboratory experiments are followed by the rolling of sheet in industrial conditions on 3600, 2300, and 5000 thick-sheet mills. The parameters that affect the front curvature of the sheet leaving the rollers are identified. The sheet-reduction conditions on the 3600 and 2300 mills are assessed, so as to determine the rolling parameters responsible for asymmetry of the process in the vertical plane. Means of compensating the sheet flexure at the roller exit are proposed.