Metallurgist (v.51, #7-8)
Use of metallurgical furnaces in recycling by E. A. Kon’kov; V. F. Egorov; M. L. Bosnyak (345-347).
This article examines the potential for recycling household wastes in the converter and blast-furnace processes. A method of performing such recycling in blast furnaces is described.
Evaluating the blast pressure of iron-aluminum thermites by I. V. Babaitsev; S. Yu. Arzhevitov; O. A. Presnakova (348-350).
When thermites or thermite-type exothermic mixtures are being prepared, the aluminum content of these materials should not be allowed to exceed the stoichiometric concentrations. Adhering to this guideline will significantly reduce the blast pressure that is generated in accidental explosions of these materials and thus prevent or mitigate the associated damage.
Radioisotope method of express analysis to determine the chemical composition of raw materials used in the metallurgical industry by V. I. Bochenin (351-355).
A two-channel radiometric method developed by the authors makes it possible to quickly determine the contents of Mo, Zr, and Fe in metallurgical raw materials with an accuracy comparable to that achieved in chemical analysis. Among the main advantages of the method is the portability of the recording equipment and the fact that the monitoring can be performed under production conditions.
Fire-resistant structural steels by Yu. D. Morozov; O. N. Chevskaya; G. A. Filippov; A. N. Muratov (356-366).
The resistance of buildings and other facilities to fire depends on the extent to which their steel structures soften when heated to the temperatures created by the fire. A steel is generally considered fire-resistant if its strength when heated to such temperatures for short periods of time remains equal to 0.6–0.7 of its strength at room temperature. The alloying system Cr-Mo-V-Nb can be used for steels that are designed to be fire-resistant up to 700° C. The greatest resistance to fire — up to 800°C — is obtained in steels that contain boron.
Simulating structure-forming processes in tube steels during controlled rolling with accelerated cooling by . Yu. Matrosov; A. A. Kichkina; A. A. Efimov; L. I. Éfron; O. A. Bagmet (367-376).
The technology of combining controlled rolling with accelerated cooling (CR + AC) makes it possible to produce thick plates having a unique combination of strength, toughness, cold resistance, and weldability. This technology is characterized by several key parameters (cooling rate, the temperature at which accelerated cooling is ended, etc.), which should be determined and substantiated from the viewpoint of the structure-forming processes that take place in the plate metal. Values of the parameters for CR + AC were obtained by analyzing the results from a study of the phase transformations and structure-forming processes which occur during accelerated cooling.
Aspects of a technology for obtaining semifinished products of low-carbon steel on a continuous section caster by S. A. Botnikov; N. N. Kuz’kina; I. S. Murzin; G. G. Mikhailov; O. V. Samoilova (377-383).
The Chelyabinsk Metallurgical Combine has mastered a technology for obtaining continuous-cast semifinished products of low-carbon ([C] < 0.10%) steels SAE1006 and SAE1008. These steels are cast in an open stream on a continuous section caster with 100 × 100 mm molds. It was determined that good-quality semifinished products and favorable casting conditions are assured by deoxidizing the steel with secondary aluminum during casting. The amount of aluminum used here is 1.2 kg/ton. The aluminum is introduced into the ladle before the ferroalloys. The value of the ratio [Mn]:[S] in the finished steel should be no lower than 22, while the value of [Mn]:[Si] should be at least 2.5. Casting speed is kept at or below 5.2 m/min, and the maximum pressure exerted on the semifinished product by the withdrawing rollers is 35 ton-f. Scanning electron microscopy and x-ray phase analysis were used to determine the composition of the sulfide compounds in the steels when the ratio [Mn]:[S] has the values 14.8 and 17.7.
Development of a production process for rolled welding wire made from Sv-08KhGSMFA alloy by A. B. Sychkov; V. V. Parusov; M. A. Zhigarev; S. Yu. Zhukova; A. V. Perchatkin; A. V. Peregudov (384-393).
Over the past few years, the Moldavian Metallurgical Plant (MMZ) has developed a Program for Development of Production Processes for High-Quality Metal Products with High Added Value and Unique Specifications. Improvement of the characteristics of rolled-wire for direct deep drawing will require the implementation of the following measures to eliminate microdendritic segregation (Cr, Mn, Si, Mo, V): electromagnetic mixing in the sump zone or secondary cooling zone; modernization of the air-cooling section of a Stelmor line, including installation of electric heaters to enable the metal to be held under isothermal conditions for long periods of time.
Impact of process factors on production of aluminum master alloys containing zirconium and scandium by S. V. Aleksandrovskii; A. R. Érdanov (394-398).
We discuss basic theory and process for synthesis of aluminum master alloys containing rare-earth metals. We study the effect of initial melt composition and synthesis temperature on the concentrations of alloying elements in the [final] alloy. We determine the composition and structure of the resulting intermetallic compounds.
Calculating the detonation parameters of mixtures of hexogen and inert additives by I. V. Babaitsev; N. V. Kozak; F. V. Antipova (401-404).
Methods have been developed to calculate the detonation parameters of mixtures of hexogen with inert additions and evaluate their reliability. It is shown that it is possible to obtain explosives with unique properties — explosives that can undergo detonation but not burn and then detonate. That in turn eliminates the chance of accidental explosions during their use.
Method of evaluating the safety of the technical system at a metallurgical plant by E. P. Pototskii; Yu. I. Gomoyunov (405-407).
Using a generalized index of operational factors to evaluate the safety of engineering systems at metallurgical plants during different periods of normal operation makes it possible to improve the safety of the plant by allowing timely and objective analysis of the condition of a given system and the implementation of operational measures designed to reduce the risk of accidents.
Nanotechnology for copper and copper alloys by Yu. N. Raikov; G. V. Ashikhmin; A. K. Nikolaev; N. I. Revina; S. A. Kostin (408-416).
This article surveys and analyzes the literature data on nanotechnologies for copper and copper alloys. It describes the main methods used to obtain nanomaterials, including powder metallurgy, crystallization from the liquid state with a controlled rate of cooling, intensive plastic deformation, dispersion hardening, and dispersion strengthening with internal oxidation. Preference is given to nanophase materials in the discussion.
Intensifying the dry magnetic beneficiation of iron ores by A. N. Koshkalda; N. V. Sukinova; V. V. Ivashchenko; E. Yu. Kovalenkova (417-419).
It is shown that it is expedient to replace worn-out and obsolete EBS 90/100 electromagnetic separators for ore-dressing by new high-intensity SBaM 0.9/1.25 separators with high-energy permanent magnets.
Effect of lime on sintering by V. M. Kurkin; M. S. Tabakov; E. A. Kashkarov; M. A. Gurkin; T. V. Detkova; S. V. Reshetkin (420-424).
To speed up sintering, improve the quality indices for the charge’s agglomeration, and reduce the consumption of solid fuel, it is best to use milk of lime and hold crushed lime with the concentrate before the sintering operation. The addition of lime to the sintering charge at the Severstal’ Metallurgical Combine is most effective when its unit consumption is within the range 20–40 kg/ton sinter.
New technological solutions to protect the lining of blast-furnace hearths by I. F. Kurunov; V. N. Loginov; S. S. Lyapin; N. S. Polyakov; V. N. Titov (425-433).
The use of schungite as a partial replacement for coke is practiced in Russia at a number of metallurgical plants, both in the production of foundry iron (its primary use) and in making conversion pig iron. The largest amount of coke is replaced when foundry iron is being made, the replacement coefficient in this case having a value within the range 0.8–1.3. Studies that included continuous monitoring of the temperature of the carbon blocks in blast furnaces with volumes of 1719, 3200, and 5580 m3 unambiguously demonstrate that the thickness of the slag crust in blast furnaces increases with the use of schungite. Protecting the lining of the hearth through the use of schungite is also accompanied by a decrease in coke consumption.
Optimizing the technology for making automobile sheet 08Yu based on the physicochemical principles of ladle metallurgy by A. I. Zaitsev; I. G. Rodionova; N. A. Karamysheva; S. D. Zinchenko; S. V. Efimov (434-445).
The main method of eliminating the possibility of having the steel contaminated by nonmetallic inclusions is optimizing the parameters of the ladle treatment on the basis of reliable physicochemical representations of the processes of refining, alloy, and finishing of the steel, the interactions of the metal and slag phases, and other aspects of ladle metallurgy. This article examines the main steps being taken in this direction at the Cherepovets Metallurgical Combine Severstal’ in the production of high-quality automobile sheet 08Yu.
Technology for the commercial production of fire-resistant steel for building structures by A. N. Muratov; Yu. D. Morozov; O. N. Chevskaya; G. A. Filippov (446-453).
The main requirements on the chemical composition and structure of fire-resistant steels are described, and alloying systems and specific procedures for obtaining rolled products of such steels are presented. The article also reports results of the trial production of rolled products of fire-resistant steels at the combine Ural Steel.
Assimilation of smelting process for electrotechnical-grade steel using a vacuum oxygen decarburization (VOD) unit by A. V. Rybkin; V. V. Ryabov; S. L. Cherepanov; V. A. Demidov; D. V. Portnov (454-455).
A process developed for smelting of electrical-grade steel enables us to satisfy customer product-quality specifications, including specifications concerning the aging coefficient.
Kinetics of shear processes in the plastic region of a billet during longitudinal rolling by A. N. Nikulin (456-461).
The development of shear processes in the billet being formed was analyzed as a function of the geometric relationships in the deformation zone. The shear processes in the deformed metal were shown to depend on a variety of process-related factors. The impact of forming conditions on penetration depth of shear processes in metal during rolling operations was discussed.
Modern vacuum equipment for scientific and industrial applications by P. A. Shpak (462-468).
A brief analysis of the vacuum equipment market in Ukraine is provided, along with a description of the potential scientific and industrial applications for addressing problems in materials science.
Physical modeling of the nozzle aerodynamics of a burner with a central body by V. V. Koptsev; O. V. Kazakov; V. N. Gorbulin (469-471).
A model of the gas feed for a burner with a central body was developed, and the aerodynamics of the gas outflow were studied on a cold model. The central-body burner developed in this paper increases the length of the gas jet by a factor of 6, thereby improving the conditions for heat exchange.