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During casting of steel, especially alloyed and high-carbon steel, in billet and bloom CCMs, segregation, shrinkage, and crystallization macrostructural defects may appear, and they cannot be completely eliminated even with rational design and process parameters. Various methods of physical action on crystallizing continuously cast ingots can be used to improve the quality of billets and rolled products. One of the most technologically advanced methods is electromagnetic stirring (EMS) of the liquid phase of crystallizing billets. The industrial CCMs currently operating in Russia and designed for the production of high-quality billets are mainly equipped with foreign-made EMS systems. Having a number of advantages, such as efficiency and commonality, such stirrers also have some disadvantages, including undismountable housing (cannot be repaired locally) and the need for several cooling circuits and boiler-type demineralized cooling water. Currently, the VNIIMETMASH Holding Company (Moscow) is the main developer and supplier of electromagnetic stirring systems for CCMs in Russia. Implementing an import-substitution program, the VNIIMETMASH has developed and put into operation mold EMSs (M-EMS), strand EMSs (S-EMS), and final EMSs (F-EMS) in billet and bloom CCMs, including horizontal ones. The stator poles are cooled with mold water in M-EMSs and with water for the process equipment in S-EMSs and F-EMSs. The coils are wo++und with a submersible double-insulated wire. A methodology for creating and testing EMS systems for billet and bloom CCMs has been developed based on theoretical and experimental studies, physical modeling, and industrial tests of electromagnetic stirrers designed by the VNIIMETMASH.

We present the analysis of the mechanism of in-service wear of the working rolls of wide-band rolling mills on an example of a 1950 mill from the casting-rolling complex of the “VMZ” JSC. We determine the main regularities of the process of wear that should be taken into account in planning roll changes in the course of operation. The performed analysis of the character of the wear profiles enables us to use a more reasonable approach to the choice and correction of sizes in the process of turning the rolls down to the required size.

A method of casting surface alloying during casting using gasified models with the formation of a wear-resistant surface layer is considered. The increase in wear resistance is due to formation of boride and carbide components by means of self-propagating high-temperature synthesis between alloyed coating components that occurs during casting manufacture. Results of comparative tests for materials under abrasive wear are presented. Data are given for material composition, structure, and hardness.

The main disadvantage of the existing sampling method of metal for hydrogen content analysis is the contact of metal with air moisture during an open overpour from a metal scoop to the ingot mold. In response, a novel method is proposed for sampling molten aluminum and its alloys for hydrogen content analysis by dipping a conical ingot mold sampler into the melt. The work was performed at the Sayanogorsk aluminum plant UC RUSAL in the technological workflow from a transport ladle to the casting machine. Hydrogen analysis results using the proposed method are compared to those of the sampling method using the Rensley chill mold. The error in the hydrogen content measurement of the sample under the existing sampling scheme with overpour of metal from a metal scoop into the ingot mold was confirmed. The hydrogen concentration in the samples taken in the Rensley chill mold is less, on average, by 0.019 cm3/100 g Al, than in the samples obtained using the newly developed ingot mold sampler. Results of the study reveal that the proposed sampling method provides an additional advantage when sampling molten metal.

The effect of silicate glassy inclusions, formed in the final stages of ladle treatment and during continuous casting, on the structural state of cast billets and the properties of rolled products made from them is conducted for low-carbon microalloyed structural steels. Nine melts of steels including three different types of chemical composition are studied. Liquid metal samples of four steel melts of the first type are taken from a casting ladle, tundish, and a continuous casting machine crystallizer. Samples from two or three melts of steels of two other types are taken from various sections along the cross-section of continuously cast billets (CCB). Light and scanning electron microscopy, and local X-ray spectral analysis are used to study characteristics of the metal macro- and microstructure, and presence of non-metallic inclusions (precipitates) within selected samples. Impact strength and hydrogen cracking (HC) resistance of rolled products made from CCB are studied. It is shown on the basis of the results obtained that formation of finely dispersed silicate glassy inclusions leads to a significant improvement in cast metal macro- and microstructure, and also the properties of rolled products made from it, primarily impact strength and HC resistance. The mechanisms, conditions, and production parameters of steel processing that control formation of inclusions based on the SiO2–Al2O3–MnO system are studied.

We present a survey of the main specific features of the continuous casting of billets of copper-based alloys with small cross sections. It is possible to significantly increase the efficiency and reduce the cost of production of lengthy semifinished products made of nonferrous alloys either by replacing the process of deformation by continuous casting or by significantly decreasing the cross sections of the billets intended for plastic metal working. It is shown that, for the major part of alloys, the process of upward continuous casting has numerous technological, economic, and metallurgical advantages as compared with other procedures of drawing. We also describe the regularities of solidification of the billets and formation of defects in the course of upward continuous casting, the specific features of design of the mold, the requirements to the properties of the graphitic jacket of the mold, and the characteristics of the modes of casting depending on the properties of the alloys.

Redistribution of carbon and other elements, and formation of the structure, composition, and properties of low-carbon Nb, Nb–Ti, Nb–V, Nb–V–Mo and Ti–Mo microalloyed steels during hot rolling is studied using metal of five laboratory melts. It is established that by selecting the temperature for the beginning of rolling in the finishing group of stands according to steel composition (microalloying system) it is possible to achieve a significant improvement in the homogeneity of the composition, structure, and set of rolled product properties. Therefore, it is demonstrated by experiment that chemical and structural heterogeneity of metal formed in the billet casting stage may be largely eliminated during hot rolling on the basis of controlling carbide (carbonitride) precipitate formation.

We considered the thermal operating balance of a continuous furnace being charged with 250 mm-thick cold steel slabs, and perform experimental measurements of the heat loss to the environment. The required heating time and peak productivity of a hot-charged furnace were determined under the assumption that the slabs were fed into the furnace at 700–1250°С. The calculations revealed that the amount of time required to heat the slabs is much shorter, productivity is higher, the amount of heat required per metric ton of metal is smaller, the amount of heat lost to the environment is lower, and the fuel (natural gas) consumption of the furnace per metric ton of metal is much lower. We also obtained a theoretical curve for fuel consumption as a function of charging temperature; according to this curve, as the charge temperature increases from 700 to 1000°C, the specific natural-gas consumption per metric ton of metal decreases from 27.7 m3 /metric ton to 10.3 m3 /metric ton, compared with 62 m3 /metric ton for cold feedstock. We find that the energy savings in heating furnaces is maximized by feeding the slabs in immediately after they come out of the continuous billet casting machine.

It is proposed to use a new submersible nozzle with eccentric apertures in order to improve continuously-cast slab quality. Calculations show that up to 38% of the heat of steel overheating is removed in the upper part of the crystallizer. The number of equiaxed crystals increases by several factors with an increase in crystallization rate. Pilot plant approval of advanced continuous casting of low-carbon and low-alloy steels makes it possible to improve hot rolled metal strength and toughness. Forecasting low-carbon steel sheet ultimate strength and relative elongation is conducted using known experimental equations. Rolled steel quality is evaluated from slabs selected from eight melts. The slab sulfur content obtained using a nozzle with eccentric apertures is somewhat higher than in slabs cast through existing nozzles.

Results are provided for a study of the effect of different microalloying systems (Nb, Nb–V, V–N) on structure formation and mechanical properties of rolled product of strength class K52 produced by combined technology of melting, casting of thin slabs 90 mm thick, and direct rolling with subsequent accelerated cooling and winding on a coil. It is shown that all of the micro-alloying versions selected provide the required strength properties, while metal microalloyed solely with niobium demonstrates the best brittle fracture resistance at low temperature. It is shown that addition of niobium to steel not only refines grain size in the metal matrix, but also changes ferrite morphology increasing the proportion of acicular ferrite, which improves steel cold resistance.

We study the operating conditions for the specialized tapping spout used to protect molten steel against secondary oxidation between the steel pouring ladle and the tundish in a continuous billet casting machine. The following are found to be the major factors affecting premature failure of the tapping spout: Localized damage to the tapping spout walls due to installation-related misalignment between the spout and the refractory-lined slide-gate valve, and gradual encrustation of the spout during the pour process, with oxygen lancing subsequently being required to remove the encrustation. The accuracy of spout alignment with the ladle slide gate can be improved by modifying the functional configuration of the manipulator to support self-alignment of the spout to its proper location. The wear on the spout can be reduced by using a pneumatic vibrator to induce vibration, and this has been confirmed by laboratory studies using a model experiment. The proposed modernization of the manipulator will enhance tapping spout operating efficiency by reducing premature tapping spout failures.

This article discusses the solution to the urgent problem of increasing productivity and reducing the energy consumption of broad strip hot rolling mills (BSHRMs) while improving the quality of rolled products. The technological capabilities of spray cooling and the use of cooling rollers whose cavities are filled with aluminum or copper balls are analyzed. The roller-cooling method is shown to have a higher prospect of solving the formulated problem, because it features good observability of the operational state of equipment, is environmental friendly, allows to improve the quality of rolled products, reduces the need for expensive reagents for cleaning the cooler, reduces energy costs by at least 50%, and allows the use of heat released by hot billets.

The authors propose a technique for predicting the conditions for the appearance of thermal fatigue cracks on the surface of rotating continuous rollers of slab continuous-casting machines (CCMs) based on the asymptotic analysis of the problem of thermoelasticity on planar deformation. The technique enables to estimate tension, displacements, and deformations in the surface layer of rollers considering the magnitude and nature of the thermal load, and the angular velocity of rotation. It can serve as the basis for choosing the material for the production of rollers, the conditions for their cooling, and the rhythm of casting. The effectiveness and justification of the proposed method are confirmed by an experiment.

The advantages and disadvantages of Russian solder 34А (Al–27% Cu–6% Si) used for brazing aluminium alloys are described. It is demonstrated that modification of solder by Sr significantly reduces the size and morphology of phases (Si and CuAl2 ), but does not have a marked affected on mechanical and production properties. The structure and properties of solder bars prepared by vacuum suction casting, hot extrusion, and continuous casting are compared. The main regimes are determined for continuous casting and hot isothermal extrusion of solder metal rods 3-4 mm diameter. It is shown that the best mechanical properties are exhibited by rods prepared by hot extrusion with a degree of reduction of 300. It is shown that the manufacturing method of filler metal rods does not have a marked effect on spreading kinetics during brazing and on the sizes of structural components within brazed joints.

This study investigates the effect of artificial aging treatment on wear performance of A356 alloy containing different amounts of Ni. Within the scope of the study, A356/Ni alloys were produced using the sand mold casting method and then the artificial aging treatment was applied. Alloys were naturally aged at room temperature for 24 hours and artificially aged at 170°C for 10 hours after keeping in solid solution for 8 hours at 540°C and rapidly cooling. The alloys produced were characterized with hardness and density measurements, microstructure examinations, and X-ray diffraction. Wear tests were performed using a pin-on-disc type testing device under three different loads and at four different sliding distances. It was found that alloy density increases with increasing Ni amount. The highest hardness value was obtained for 1% Ni added alloy, and an increase in hardness was observed with the addition of Ni. The lowest weight loss was obtained for 1% Ni added alloy, which also had the highest hardness, and it was observed that the addition of Ni led to an increase in weight loss.

A model has been developed for predicting the metal temperature in the specified superheat range above the liquidus temperature inside the tundish of a continuous casting machine (CCM) depending on the last temperature measurement in the steel-pouring ladle (prior to casting), as well as ladle history and secondary steelmaking process under the conditions of the Casting and Rolling Complex (CRC) of the JSC “Vyksa Metallurgical Plant” (VMZ). It is suggested to predict the superheat temperature of steel at the CRC by using statistical models considering the specifics of technological process. During the first stage, the model itself has been developed by integrating the following two approaches: a machinelearning algorithm and probabilistic graphical model (PGM and Bayesian networks). The first approach provides the point estimate of the intermediate and final temperatures of the specific melting, while the second approach allows evaluating the probability distribution. The PGM-approach is very promising in the situations involving missing, incorrect, or undefined input data, which are quite common at the metallurgical plants. During the first stage, the achieved level of accuracy of tundish temperature prediction was 6.0°C. During the second stage, the model was integrated into the shop automated process control system, which allowed increasing the prediction accuracy and ensuring a real-time control of the process parameters. The model is used as a guidance (master) tool for the process personnel operating the ladlefurnace and vacuum degasser equipment.

A mold oscillating system for continuous casting machines has been developed based on a nonsinusoidal oscillation profile with an online oscillation control capability. A new type of the mold oscillating system is proposed comprising two servomotor-driven eccentric shafts. The principle of operation of a non-sinusoidal oscillation system is described. Based on the analysis of the non-sinusoidal oscillation waveform expressed as a piecewise linear function, the angular speed of a servomotor necessary to realize such oscillations was determined. A procedure for calculating process parameters was developed. The model of synchronized control of the casting speed and oscillation frequency was optimized and process parameters were calculated for the deviation factor of 20% and amplitude equal to 4 mm. The mold oscillating systems of sinusoidal and non-sinusoidal type were compared. The advantages of the non-sinusoidal type of oscillating system were shown, which include a decrease in depth of the oscillation marks on the surface of continuous-cast billet, an improvement in the mold-ingot lubrication conditions, and higher quality of continuous-cast billets.

Square steel billets (with cross sections 100 × 100 mm and 150 × 150 mm) cast on a continuous-bar-casting machine (CBCM) have a mass-averaged temperature of 1000–1100°C after gas cutting, resulting in considerable interest in storing the sensible heat from the billets in a thermostat for subsequent use in the reheating furnace. We describe a mathematical model of the thermal conditions in the square steel billet during solidification in a CBCM and cooling in air when contained in a thermostat and when heated in a furnace. We also describe theoretical results for the temperature field in the billet along the CBCM–thermostat–reheating furnace process train under several reasonable post-continuous-billet-casting-machine (CCM) heat treatment scenarios.

On the basis of proceedings of an international symposium on casting and rolling complexes the latest solutions for hot-rolled strip production by a combined process of continuous thin slab casting and rolling are reviewed. Advanced developments in the field of equipment and technologies are presented. The main tendencies and future tasks on this subject are noted.

We discuss the operating principle and design features for an improved mechanical flux feed system to be used in continuous slab-casting machine molds; this system provides increased reliability and operational efficiency, and is easier to maintain. We describe experimental results for the operating parameters of a combined drive for use in such a mechanical flux feed system, as well as validation of the design, kinematic and power consumption parameters for such drives.

Results are provided for a comprehensive study of the structure and properties formation of microalloyed pipe steel produced in an AO United Metallurgical Company (Vyksa) casting and rolling complex conducted under laboratory and industrial conditions. The features of structure formation established are used to create steel compositions for electrically welded pipes and coiled rolled product manufacturing technology corresponding to steels strength classes up to K60 with improved toughness and cold resistance.

A new electromagnetic metal level sensor for a billet mold is considered in comparison with radioisotope level sensor. Comparative characteristics of the sensors in the process of casting with oil were obtained during demonstration testing of electromagnetic sensor at two metallurgical plants. In the process of operation, it was shown that electromagnetic metal level sensor has somewhat better characteristics as compared to radioisotope sensor. Utilization of electromagnetic sensor instead of radioisotope sensor allowed reducing the fluctuations of metal level and withdrawal rate in comparison with stabilization based on the radioisotope sensor at both plants.

Technology is developed combining continuous vertical casting of metals with simultaneous deformation, and the device operating principle and implementation of this technology are described. Data are provided for the design features and functioning of the device. Results of experimental studies of AD0 and D16 alloy billets are provided. It is shown that this technology makes it possible in a short production cycle to prepare long metal objects at a rate of 2 m/min. The blanks obtained exhibit a fine-grained structure with a grain size not exceeding 7 μm, and also increased hardness, inferior to the maximum possible by 23%.

We analyze the processes of modification and refinement of a melt in a casting ladle from the viewpoint of the nature, possibilities, and efficiency of their influence on the metal. The hydrodynamic processes running in the ladle are analyzed in detail by means of the physical simulation. The analysis of the results of simulations and the obtained approximate analytic model is performed for the improvement of the procedures of refinement and modification.

We consider thermal processes running in the course of cooling of a continuously cast ingot in a continuous billet casting machine with regard for the heat of phase transformations. For the solution of the problem of rational utilization of the heat of melts, we propose to improve the technology of continuous casting of steel, which would make it possible to use the heat of the liquid core of an ingot for leveling the temperature field over its cross section and guarantee the minimum losses of the heat at the exit of the continuous billet-casting machine. We develop a mathematical model of cooling of continuously cast ingots in a two-dimensional space representation with regard for the release of the heat of crystallization in the two-phase zone. The numerical realization of the model is performed with the help of the implicit difference scheme of coordinate-wise splitting. The adequacy of the model is checked by analyzing the convergence of the experimental and numerical data according to the Fisher, Student, and Mann–Whitney criteria. In modeling, we simulated the control action in the zone of secondary cooling. It is established that, in the case of application of the control action in this zone, the surface temperature increases by 160°C, while the average mass temperature increases by 100–160°C. We choose criteria for the rational modes of cooling of continuously cast ingots. To preserve the heat content of an ingot, it is proposed to use heat insulation after the zone of water–air cooling. We determine relationships between the parameters affecting the surface temperature of the ingot and represent them in the form of nomograms. It is shown that, before the machine of gas cutting, as a result of heat insulation in the zone of air cooling, the ingot is thermostatted as a result of which the temperature of its most vulnerable zones (corners and surfaces) increases. It is established that, for the rational modes of casting of steels, the ratio of the length of the zone of heat insulation to the total length of the continuous billet casting machine varies within the range 0.3–0.6. To determine the heat losses in the process of subsequent cooling of the ingot in air after leaving the zone of machine gas cutting, according to the existing technology of transportation of slabs to compression, the time of modeling was set equal to 90–105 min. To preserve the heat content of the ingot and level temperatures over its cross section, it is also necessary either to use a thermally insulated transmission roller conveyer or to hold ingots in a thermostat.

Research is conducted within the scope of the Clean Steel project into reasons for variation of the metal level in a crystallizer and breakouts of the crystallizing metal skin in a thin-slab CCM, and also a study of reasons for defect formation in hot-rolled strip. Examples are provided of improved monitoring and control of the VMZ casting and rolling complex (CRC) technology. Implementation of the monitoring production technology – evaluation of metal product quality – operational adjustment of technology concept makes it possible to reduce the CCM emergency situation index to less than 0.5 ton/105 tons of steel, and also to determine factors influencing the formation of transverse cracks over a rolling mark, and to remove defect formation.

The work is devoted to development of a new design of horizontal continuous billet casting machine (HCBCM) for non-ferrous and precious metals. The possibility of calculation and design of horizontal casting machine elements by means of computer simulation using the software created is demonstrated. Based on the proposed methods of calculation and design as well as analysis of mathematical modeling results, new designs of HCBCM elements are created that enhance the efficiency of the machine. Appraisal trials of HCBCM structural elements created are performed successfully to measure the effectiveness of this work and introduction into production.

Technology is developed for preparing semifinished sheet of hypereutectic alloys based on the aluminumcerium system intended for operation under conditions of x-radiation. The technology is based on creating a test alloy by casting and subsequent deformation treatment. Two versions of cast billet preparation are considered in the work. Sheet material prepared by rolling these billets exhibits good adaptability and may be used for producing engineering objects.

Nonmetallic inclusions in steel such as oxides, silicates, aluminates, spinels, etc. substantially reduce the quality of metal. They are mainly introduced by the slag formed on the metal surface of a doublestrand plant. It is proposed to separate the slag from the metal using a special perforated tube installed on the refractory pocket block of the ladle bottom and fixed with gunning mix. The use of this device for continuous slab casting ensures the high quality of hot- and cold-rolled sheets.

The most important recent updates for the ProCAST casting simulation software are reviewed. The new modules for process optimization, electromagnetic stirring simulation, new process definition wizards in the Visual-CAST pre-processor, etc., are described.

Results are given for research aimed at improving the quality of large tonnage flat ingots under RUSAL Joint Company (Krasnoyarsk) conditions as a result of reducing the hydrogen content within them to less than 0.1 cm3/100g. For this purpose, under production conditions the change in molten aluminum alloys series 1XXX hydrogen content is analyzed in the main stages from the aluminum electrolyzer to the casting machine. Production operations are determined within which there is significant melt impregnation with hydrogen. Research precision is provided by using a developed procedure for molten sample collection in the main production operations and considering the specific nature of production. Technical solutions are proposed from research results aimed at reducing melt hydrogen expansion.

Physicomechanical and casting properties are studied for high-phosphorus irons used in the assembly of aluminum electrolyzer baked anodes in RUSAL enterprises compared with gray cast iron containing a minimum amount of phosphorus and sulfur. It is shown that iron primary crystallization under conditions approaching pouring production parameters and iron cooling in the nipple – cast iron – carbon anode contact assembly proceeds with significant supercooling that causes the formation of a pearlite matrix in the cast iron structure with increased hardness. Iron with a lower carbon equivalent exhibiting high hardness has a better elasticity modulus and strength values. The presence of ternary phosphide eutectic within the iron structure with a high phosphorus content reduces the breaking strength considerably at high anode operating temperatures and this may be a reason for cast iron loss of strength and anode separation at the end of an operating cycle leading the electrolyzer stoppage. Iron with the minimum phosphorus content exhibits strength exceeding by more than a factor of two that of high-phosphorus cast iron and also the least electrical resistance in the range up to 500–600°C. In addition, iron with a high phosphorus content has an anomalous change in linear thermal expansion coeffi cient (LTEC) in the range 600–810°C that may also lead to degradation of “soft” metal (anode at the end of an operating cycle). The results obtained are explained drawing on thermal analysis data and metallographic studies.

The effect of structural defects of wrought semifinished products of vacuum-induction melted alloy KhN55MVTs-VI on service properties is studied. As a result of analyzing the structure using electron microscopy, microdefects have been detected that have an unfavorable effect on alloy ductility. It is established that defects are metallurgical in nature and of casting origin, and they form on aluminum oxide particles distributed through the whole volume of a workpiece. It is demonstrated that vacuum-arc remelting after vacuum-induction melting provides the absence of microdefects of this nature.

A method of using sensible heat of hot steel slabs issuing from a continuous casting machine (CCM) in which it is possible to eliminate slab heating in furnaces prior to rolling. For this, hot slabs at a certain time are sent to a thermostat, where the temperature is equalized along their section and length, whereupon the slabs can be fed to the rolling mill. This achieves a significant savings of fuel and eliminates heating and oxidation of the metal in the furnace. To implement this method, one must first solve several problems: put the continuous casting machine on one technological line with the rolling mill and establish diagnostics for surface quality of the slabs directly on the exit from the continuous casting machine. In addition, it is necessary to have a fairly accurate mathematical model to calculate the slab temperature field for stationary and non-stationary modes of casting. The mathematical model proposed in the article is somewhat simplified and serves mainly for the communication of the main ideas.

Results are given for industrial approval of production under casting and rolling complex conditions within the composition of a joint metallurgical company of rolled coil for tube of strength category X70 without adding niobium for three microalloying systems (V–N, V–Ti–N, V–Ti). It is shown that in order to prepare rolled coil of strength category X70 without additional specifications according to Charpy and DWWT tests at negative temperature the most suitable steel system is microalloying with vanadium and nitrogen (V–N system).

The effect of pipe billet production technology and of the order of introducing rare-earth elements and calcium on nonmetallic inclusion composition and morphology is studied. The correlation of inclusion morphology with corrosion resistance and casting suitability for steel in a CBCM is evaluated.

Advanced technology has been developed for the production of HSLA steel heavy plates over 60 mm thick made from concast slabs. This technology provides steel band feeding to the concaster mould liquid pool by a specially designed device. The developed technology is a convenient tool for optimization of the casting macrostructure. Minimization of the axial segregation and heavy plate Z-direction mechanical property improvement were realized even if the reduction ratio was less than 2–3. The ductility in the Z-direction of heavy plates was increased by 15–20%, and the toughness of heavy plates was increased by 1.5–2.0 times. High level yield (97.5–99.5%) was reached for heavy plates by the implementation of steel band feeding on the basis of ultrasonic tests using European standard SEL 072 class 1–2. Therefore, steel band feeding is an appropriate alternative to soft reduction and electromagnetic stirring technologies for heavy HSLA steel plates.

It is established that structural inhomogeneity of 20-KSKh steel rolled product produced in the casting and rolling complex at OMK-Stal is caused by presence of bainitic areas within a ferrite-pearlite matrix. Differences in this inhomogeneity are shown due to banding of the ferrite-pearlite structure, determined according to GOST 5640. A method is proposed for evaluating the degree of structural inhomogeneity (banding number) containing bainitic areas. Comprehensive corrosion tests are performed for specimens with “bainitic” and ferrite-pearlite banding. It is established that specimens with “bainitic” banding exhibit better corrosion resistance.

The Russian and foreign technology used since the beginning of the last century to industrially produce collector profiles made of copper-cadmium bronze is characterized by low productivity, large losses of metal, and semifinished and finished products of inferior quality. The technology includes casting and pressing ingots obtain semifinished products of trapezoidal, square, or rectangular cross section, which are then rolled or drawn to obtain billets for subsequent final drawing. The pressing and rolling or drawing of the trapezoidal semifinished products is accompanied by bending of the ribs and twisting of the product, and the quality of the finished profiles is compromised by their curvature. The authors have developed new methods and equipment for rolling collector profiles in tapered rolls to avoid the formation of such defects. Results are reported from tests of the methods, which involve rolling in tapered rolls with intersecting axes.

To eliminate the problems of existing direct-chill molds (DCMs) used to cast ingots of complex-alloyed bronzes and brasses, an original design of DCM has been developed and introduced into production. The new mold solves the following problems: it facilitates the assembly, installation-dismantling, and use of DCMs, simplifies the system that supplies the mold with coolant, increases casting speed for alloys that are susceptible to hot-shortness, and makes the operation of the mold more reliable as a whole.

A study is made of the effect of the depth and shape of the liquid crater in a continuous-cast ingot on the parameters of the casting operation. Sensitivity functions describing the location of the phase boundary are constructed for a two-dimensional mathematical model to determine the temperature field of a wide slab. The functions are constructed with the use of Stefan conditions for an unknown boundary. Results are presented from calculation of the effect of variations in casting speed, secondary cooling, geometric parameters, and thermophysical parameters on the depth and shape of the crater.

Results are reported from studies of the conditions of solidification, cooling, and heating of steel ingots cast in ingot molds. It is shown that optimizing the length of time between the casting of the ingot and its charging into the heating furnace can significantly shorten the heating period and thus increase the unit productivity of the furnace, reduce metal loss from oxidation, and decrease unit fuel consumption.

Intermetallic alloys, created on the basis of Ni3Al compound, may be used up to 1200°C, retaining high thermal stability. These materials are used in aviation gas turbine construction. Contemporary single-crystal casting technology for high-temperature alloys makes it possible to prepare billets with different crystallographic orientation, and this provides a significant difference in mechanical properties. Low-cycle fatigue (LCF) resistance is studied under test conditions with controlled deformation in a loading cycle at 850 and 1050°C for intermetallic alloy based on Ni3Al with different crystallographic orientation. The effect of temperature and crystallographic orientation on LCF characteristics is studied. It is demonstrated that at both temperatures one of the orientations shows better results.

An improved design of tundish which has chambers for the plasma heating of liquid steel has been developed and tested. The design of the tundish improves heat and mass transfer processes inside it. The new design elements of the tundish accelerate the entry of the metal into zone occupied by the high-temperature plasma in order to improve the conditions for its heating and making the metal’s temperature uniform throughout the volume of the tundish. Two tundishes of the new design were made and the plasma heating unit was factory-tested during the casting of steel on continuous caster No. 4 in the oxygen converter shop at the Magnitogorsk Metallurgical Combine.

This article describes the trial use of a new integrated technology for pre-production casting in sand-clay molds. Virtual modeling of the casting operation is performed, the casting is designed, and the casting regimes are determined. A master model of the casting is constructed with the use of 3D printing. Non-contact optical scanning is used to check the geometric characteristic of the plastic master model and the actual casting made from it.

This article presents an example of the end-to-end simulation of the casting of a steel ingot in an ingot mold and solid forging of the ingot. The simulation is performed using the software products ProCAST (ESIGroup, France) and QForm (Quantor Form, Russia). The formulation and solution of problems is examined and data are obtained on the temperature field and shrinkage defects of the ingot. The effects of these factors on the metal-forming operation are taken into account in the solution of the problems.

Given the stiff competition that exists in the current market, the quality and speed with which orders are executed are of decisive importance in gaining the advantage over other market participants. The automated design of technologies for making cast semifinished products and real-time correction of their parameters at the design stage are among the prerequisites for successfully competing in today’s metallurgical industry. An actual production process used to make cast steel semifinished products is analyzed in the system ProCAST to illustrate the possibility of reducing the amount of time that has to be spent on designing the casting equipment.

Questions are considered for pouring steel in section continuous billet casting machines (CBCM). Structural elements are developed of a unit for protecting the metal stream during steel pouring in a section CBCM that facilitates a reduction in reaction of air with molten steel during pouring and provides rational argon supply parameters into a refractory pipe annular groove. This makes it possible to increase pouring stability and provide high quality poured metal.

The casting of steel on a continuous caster is the culmination of interactions that take place between the pouring equipment, mold, secondary cooling zone, and ingot withdrawal mechanism in a single process. Studies of the continuous casting of steel have shown that the stability of the continuous casting operation should be evaluated based on the criterion of lead time. Gaps in the components of the caster have a direct effect on the velocities of the mold and the ingot, which in turn determine the lead time. Hundreds of continuous-caster strands equipped with mold oscillation mechanisms of the hinge-lever type and hinged multi-component dummy bars have been in use in many countries up to the present. Thus, the effect of gaps in the caster components that determine the quality of the cast semifinished product is an important problem and needs to be resolved.