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by Academician Leopold LEONTYEV, Director of the Metallurgy Institute (IMET), Ural Branch, Russian Academy of Sciences; and Vladimir PONOMARYOV, IMET Academic Secretary
Towards the end of the 1920s the Urals became a booming industrial region of this country. And so there was a felt need for an adequate R&D base. Accordingly, the Academy of Sciences of the USSR opened its branch in the Urals in January 1932. Research scientists involved with metallurgy figured prominently there...
One of them was Vladimir Mikhailov, full member of the Academy of Sciences of Kazakhstan-a man who initiated basic research into comprehensive uses of multicomponent mineral wealth in the Urals. Working side by side with him was Dr. Nikolai Diyev, a pioneer in the theory and practice of nonferrous metallurgy.
We might as well name a galaxy of outstanding scientists wedded to their cause. For one, Grigory Chufarov, Corresponding Member of the USSR Academy of Sciences, has made a major contribution to the advancement of academic science in the Urals. His theory of oxide metal reduction has found broad practical application. He has suggested many innovative methods and techniques. For instance, using a sulphuric acid solution for pickling; or a technique of decarburization in prehydrogen firing to improve the ferromagnetic characteristics of transformer and dynamo steels; these methods are employed at the Verkh-Isetsk Steel Plant in Yekaterinburg, the capital of the Urals. Early in the 1960s Dr. Chufarov's laboratory pioneered in a new line of research, the thermodynamics of ferrites; accordingly, appropriate methods and techniques had to be designed for the purpose (X-ray, magnetic, electron-diffraction ones). Grigory Chufarov's pupils and followers then carried out extensive physicochemical studies into the complex oxide systems of transition metals (ferrites, man-ganites, aluminates, titanates, etc.) with a structure of spinelite, garnet and perovskite. (*) These research findings are being used in the production of various types of engineering ceramics, specifically, at the Astrakhan- based engineering plant Progress.
Today this work is carried on by Dr. Vladimir Balakirev, Corresponding Member of the Russian Academy of Sciences. His research team has designed high-temperature superconductors and studied their characteristics. Of particular interest here are manganese-containing materials: their electric resistance can change severalfold under the action of a magnetic field, a phenomenon known as the magnetoresistance effect.
Dr. Oleg Yesin (Technology) is a trail blazer in a fundamental research trend at the IMET Institute-the structure and properties of metal melts. His electrolytic theory of slags has allowed to predict and realize new technological processes in metallurgy, say, obtaining metal from oxide melts by means of electrolysis. Simultaneously, Dr. Yesin became involved with oxide melt polymers and with the application of model theories to metal substances. Attacking this range of problems further, Academician Nikolai Vatolin founded a scientific school concerned with the structure and physicochemical features of liquid metal and oxide systems, i.e. problems that are of paramount significance for an insight into the nature of liquid state and for improving technological processes in metallurgy as well. Extensive studies were carried out into the structure and sensitivity characteristics of the above systems (viscosity, magnetic susceptibility, electric conduction, density, surface tension, heat of mixture). It thus became possible to classify them according to their composition and characteristics. Studying the effect of a liquid metal density increase under the cumulative action of direct current and electromagnetic field, IMET researchers developed a technology for cleaning liquid metals (iron, tin) from foreign inclusions.
Academician Nikolai Vatolin and RAS Corresponding Member Edouard Pastukhov, the authors of an innovative method of X-ray analysis at high temperatures (up to 2,000C), have obtained experimental evidence on a change of structural characteristics of a large group of liquid metals depending on the degree of heating. The hysteresis (**) of the structure and, consequently, of melt characteristics-a phenomenon discovered thereby- explains how the thermal treatment of melts acts on the quality of castings and why.
Proceeding from their X-ray analysis data and using a variety of methods, IMET researchers have determined the electric conduction, surface tension and thermodynamic properties of metals. Another method-that of computing the potentials of molecule/atom interaction-has enabled Dr. Vatolin and coworkers to use computer simulation for interpreting the topology of amorphous and liquid metals and alloys, and for predicting their physicochemical characteristics under various conditions.
As good as all the IMET laboratories zero in on comprehensive utilization of alternative metal raws (in particular, on the physicochemical characteristics of associated processes). This is a priority research and
* Minerals of the subclass, of complex oxides. - Ed.
** Hysteresis - lag of a physical quantity that characterizes the state of a substance (magnetization of ferromagnet, polarization of ferroelectric, etc.) from another physical quantity that characterizes external conditions (magnetic and electric field strength). - Ed.
technological trend. The point is that iron ore deposits in the Urals are depleted, while this area has a huge wealth of titanomagnetite rocks, brown iron ores and ferriferous bauxites with alumosilicate inclusions of siderites (*); there are billions of tons of such deposits and quite a lot of red slime (mud), (**) the wastes of alumina preparation. Joining hands with the Ural Institute of Metals and the Nizhni Tagil Metallurgical Plant, we have developed a new technology, the world's first: smelting low-silicon vanadium-containing cast iron from complex titanomagnetite ores mined at the Kachkanar deposit. Such cast iron is produced in large blast furnaces. The slag obtained by the cast iron blow in converters is a raw from which vanadium can be recovered using a special technology. Tackling this range of problems, Academician Leopold Leontyev and Dr. Sergei Shavrin (Technology) have suggested an original mode of preparing iron-ore materials for the process stage in a controlled atmosphere. Simultaneously, IMET research teams (under Dr. Shavrin, Academicians Vatolin and Leontyev) and their colleagues from industrial R&D centers have substantiated the idea of a low-waste technology and made a feasibility study of a project to set up an industry that will be using titanium obtained from complex ores (containing ilmenite, titanium and magnetite) for the manufacture of a variety of articles. This project, if realized, will enable Russia to produce pigment titanium dioxide that goes into the making of safe technical dyes resistant to high temperatures, metallic titanium, high-quality alloyed steel as well as vanadium-related products. This industry can be launched at a titanium-magnesium enterprise in Berezniki, and at steel plants in Chusovo and Novoalapayevsk.
Two technologies have been offered for processing oxidized nickel ores of the Serov deposit and extraction of iron, nickel and chromium. Using the first technology, from the cast iron smelted at the Serov Plant (containing 6 to 9 percent nickel) one can melt out a wide range of chromium-and nickel-containing steels without costly nickel or else with a minimum expenditure of it. The other technology provides for selective extraction of ferronickel and chromous products in the process of sequential reduction without metallurgical coke (this way waste-free iron is obtained in such units). In both technologies we get slag as the end product from which glass of various shapes and ferronickel (containing up to 70 percent of nickel) can be obtained. In fact, ferronickel can well substitute for metallic nickel still being used as dopant in metallurgy. The prime costs of the new product are only 20 percent of those involving orthodox nonecological technologies with the use of sulphurizing.
The IMET Institute also focuses on technologies for such raws as siderites mined at Bakal (Chelyabinsk region), titanium-containing leucoxenes, (***) ferroalumina, red mud...
In another area of nonferrous pyrometallurgy, the focus is on optimizing the processing of composite polymetal raws and wastes of the metallurgical and chemical industries. Here essentially new technologies are being developed for comprehensive waste-free processes with respect to sulphide copper, copper/zinc, copper/nickel, nickel, pyrite concentrates and pyrite cinders with extraction of nonferrous and rare metals in matte (****) and in sublimate, (*****) and simultaneous isolation of iron in lime slag, a substance that can be used in the cement industry and in ferrous metallurgy as a raw with preassigned physical and chemical properties. Among other IMET-developed innovative technologies mention should be made of techniques for the processing of oxidized complex-metal material: first, nonferrous and rare metals are smelted in an alloy (where iron is present), and then they are extracted on a selective basis. Some of these findings have been incorporated in state-of- the-art technologies in mineral raws processing in the Urals and the Far East.
Other IMET - designed techniques likewise hold good promise from a practical angle. One such technology has been suggested for the Kirovograd and Krasnouralsk copper-smelting enterprises: a low-waste processing of pyrate concentrates and other pyrate-containing products of nonferrous metal ore dressing; this technology makes it possible to sublimate as much as 94 percent of sulphur into gases, and smelt 90 to 95 percent of copper
* Siderite-a mineral of the carbonate class.-Ed.
** More on that, in: V. Koroteyev, "The Urals: 20th Century Discoveries", Science in Russia, No. 3, 2000.-Ed.
*** Leucoxene-fine-grained (cryptocrystalline) mineral mixtures of titanium oxides (rutile, anatase, less often brookite) and/or sphene (titan-ite) mixed with quartz, ilmenite, iron and manganese hydroxides, Qic.-Ed.
**** Matte-an intermediate in the output of some nonferrous metals (copper, lead, nickel, etc.); namely, this is an alloy of nonferrous metal sulphides and iron.-Ed.
***** Sublimate-product of sublimation, a process whereby solid body is transformed into a gaseous state bypassing a liquid stage (what is known as the phase transition of the first order).-Ed.
and 85 to 90 percent of silver to matte. Iron and nonmetalliferous components are transferred into slag and then isolated. Work is in progress to see about possible uses of copper ore from the Barsuchy Log deposit as a sulphurizing agent in nickel-rock blast smelting at the Yuzhuralnickel mill. Likewise, a new idea for a comprehensive processing of copper/zink and off-balance copper ores is under study.
Yet another novel technology developed at IMET: that of processing the powders containing copper, tin, zinc, arsenic as well as rare and noble metals; and, as an important sideline, matte- and sublimate-processing. Here heavy nonferrous metals are reduced in an ionic melt of salts. IMET engineers have designed a unit for such kind of processing as well.
One of our researchers, Dr. Hermann Moiseyev (chemist), is involved with important problems. Among other things, he is engaged in basic research with the aim of
forecasting interactions in multicomponent heterophasic systems; in experimental studies into how to utilize non-ferrous metallurgy wastes by means of ionic melts as reaction media. Dr. Moiseyev and his team have come forward with practical recommendations for waste processing and extraction of valuable components thereby.
Yet another research scientist, Dr. Vladimir Zhuchkov (Technology), is exploring in the field of complex ferroalloys that contain niobium, vanadium, titanium, magnesium, manganese, rare-earth metals and other components. He has found combinations of optimal dopants for specific qualities of steel.
His colleague, Dr. Georgi Kozhevnikov, has identified the role of intermediate phases and compounds in the reduction of metals and alloys. Using these findings, he has developed techniques of obtaining pure silicon as well as calcium and silicon carbides. In a different field, Dr. Kozhevnikov has developed a technology whereby peat could substitute for charcoal in coal-burning processes.
Dr. Viktor Vorobyev (Technology) meanwhile has designed a computer-aided system of automatic control for ferroalloys in electric furnaces. This system collects, analyzes and synthesizes a qualitatively new array of data on the condition of the burden (charge), electric arc and
melt. The main parameters of the process (positions of the electrodes, excess or shortage of the carbon, composition and quantity of the melt) are fed nonstop on the display; if need be, these parameters can be corrected at once. Tested in the furnaces of the Chelyabinsk- based electrometallurgical mill, this system can be applied at other ferroalloy mills in Russia as well.
Led by Dr. Vladimir Bulanov (Technology), an IMET research team in the late 1970s conceptualized processes of obtaining powders, composite materials and powder coatings from dopant-containing raws available in the Urals. The physicochemical and thermodynamic models of melt dispersion have made it possible to design technologies for the output of low- and medium-doped powders on the basis of iron, ferroalloys and nonferrous metals; such powders can be produced at preset characteristics. Besides, it has become possible to obtain composite materials from iron powders supplemented with oxides, carbides, borides and nitrides. Such polycomponent raw materials and special methods of formation and sintering have given rise to a range of materials with predetermined characteristics. All that means significant economy over conventional techniques. The powder production has been brought to a commercial level: powders are produced for structural and friction-free materials, filters, drilling-rig brakes, protective and hardening coatings. Work is underway to develop powders for machinery and equipment employed in the rigorous conditions of the Far North.
And yet another area of research-gaseous-phase metallurgy-features prominently in IMET activities. Here a research team under Dr. Irina Frischberg (Technology) has conceptualized a method of obtaining high- and ultradisperse powders; this method is based on the processes of evaporation and condensation of metals from the gaseous phase. By now several generations of commercial apparatuses have been put into service. For instance, the VMP firm has helped IMET set up a small pilot shop for the production of zinc, copper and bronze powders, and of related items, including antirust preparations for galvanizing steel structures by the cold process-namely, the two-component corrosion preventive compound of the TsVES brand and its monocomponent analogue, TsINOL. In service life such coatings are not at all inferior to conventional ones made by means of galvanizing by the hot process. Another advantage: they involve much lower costs and labor. The plastic lubricant of the VYMPEL trademark produced here has been found particularly good for heavily loaded units in machines used in the working of shafts with a mass of up to ten tons.
Dr. Frischberg and her team are designing other high-performance technologies in gaseous-phase metallurgy. One such process is being used in continuous gas/phase galvanization of thin cold-rolled steel sheet, rolled stock (bar) and reinforcement.
As we see, academic science is doing quite a lot in designing innovative state-of-the-art techniques for the metallurgy of the Urals and other regions of this country.
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