Рейтинг
Порталус


DURABLE WIRES

Дата публикации: 01 октября 2021
Автор(ы): Marina KHALIZEVA
Публикатор: Научная библиотека Порталус
Рубрика: ВОПРОСЫ НАУКИ
Источник: (c) Science in Russia, №2, 2012, C.46-51
Номер публикации: №1633075547


Marina KHALIZEVA, (c)

by Marina KHALIZEVA, journalist

 

The specialists of the Moscow High-Technology Research Institute of Inorganic Materials named after A. Bochvar-a major scientific center of the Rosatom State Atomic Energy Corporation-created manufacturing technology of electrical wires from a new class of materials with a nanometric level of structural dispersion, possessing a unique combination of durability and conducting properties. Their practical application will provide a qualitative breakthrough in electrical, aviation and space technology, mechanical engineering, shipbuilding and electronics.

 

Main types of superstrength nanostructured wires produced by the High-Technology Research Institute of Inorganic Materials named after A. Bochvar.

 
стр. 46

 

Physical effect of abnormal increase of durability in thin wires of the Cu-Nb system.

 

 

The institute, which participated in the creation of the nuclear shield of the country, atomic navy, modern atomic power plants, space vehicles and high-technology production of spent nuclear fuel reprocessing in the second half of the 20th century, set about to deal with superconductors* in the 1960s. At that time, the Kurchatov Center (today the Russian Scientific Center "Kurchatov Institute") developed unique magnetic systems--tokamaks-the most promising equipment for retention of plasma**. The temperature needed for achieving of thermonuclear fusion in tokamaks was to be raised to hundreds of millions of degrees. But how one can control such physical element? In 1951, outstanding Soviet physicists Andrei Sakharov*** and Igor Tamm suggested a thermonuclear reactor for this purpose, in which plasma could have the form of torus and retained in the latter by means of strong fields created by magnets with superconducting coils. The institute headed by the well-known metallurgist Academician Andrei Bochvar (1902-1984) was engaged in search of new materials for them in close cooperation with the Kurchatov Center.

 

It was there that approximately 10 t of superconductors based on niobium-titanium (NbTi) alloy were produced by galvanic fusion for the T-7 plant (1979)--the world's first tokamak, and the so-called "bronze" technology of composite production from niobium-stannic compound (Nb3Sn) based on selective solid-phase diffusion was developed and mastered on an industrial scale. Thin niobium filaments were pressed into a bronze matrix containing 10-13 percent of Sn. The multiple drawing and repeated press-fitting with intermediate annealing and consequent thermal treatment resulted in diffusion of tin into niobium and formation of a thin protective Nb3Sn film. Actually copper did not penetrate into niobium due to its negligible solubility. Thus manufactured wires possessed high ductility, were easy to bend and were laid in a cable preserving their strength. Owing to the innovative technology Bochvar's colleagues actually cleared the way for creation at the Kurchatov Institute of a major magnetic system T-15 (1988) consisting of approximately 25 t of winding wire. It was the world's first large-scale application of superconducting materials. Today Bochvar's followers provide long-length high-current windings based on Nb3Sn compounds for model coils of the international thermonuclear experimental reactor ITER* under construction in France.

 

Design optimization of such cables, improvement of characteristics of constituent alloys led eventually to the emergence of a new class of composite materials and also to the creation on their basis of industrial technology of making nanostructural electrical wires with a unique combination of strength and electroconductive properties. This work carried out under supervision of Viktor Pantsyrny, Dr. Sc. (Tech.), is among the breakthrough achievements of Bochvar's colleagues.

 

By means of assembly of bimetal composite billets and their consequent deformation the metallurgists managed to introduce band niobium fibers 6-10 nm thick into copper matrix of a standard wire. The specialists implanted over 400 mln of such fibers evenly distributed along the axis of a conductor into a cable with 2x3 mm section. These fibers guarantee mechanical strength

 

See: V. Sytnikov, V. Vysotsky, "Superconducting Technologies in Power

 

Engineering", Science in Russia, No. 2, 2010.--Ed.

 

** See: V. Strelkov, "No Royal Ride in Thermonuclear Research",

 

Science in Russia, No. 1, 2009.--Ed.

 

*** See: "Father of the 'Hydrogen Bomb'", Science in Russia, No. 4, 2011.--Ed.

 

See: V. Glukhikh et al., "On the Brink of Thermonuclear Era", Science in Russia, No. 3, 2003; L. Golubchikov, "Tokamak--International Challenge", Science in Russia, No. 1, 2004.--Ed.

 
стр. 47

 

(1,200-1,500 M Pa) to a product at a level of steel. Besides, a small distance between fibers comparable with an average length of the electron path in a matrix, provides electric conductivity close to pure copper. Moreover, the new windings are ten times more resistant to bending stresses by contrast to Cu. Such technology makes it possible to produce high-strength wires of identical properties 100-200 m long.

 

It should be stressed that the Western electrical companies, in particular, Supercon (USA) and also Showa and Furukawa Electric (Japan), tried to produce a power cable similar by characteristics in late 1980s-early 1990s, but only our scientists managed to achieve an optimum ratio of strength and electrical conductivity. The consignment of national nanocomposites was sent to the scientific centers of the USA, Belgium, the Netherlands, Germany, Poland and Lithuania and received high appraisal of foreign specialists. For example, the specialists of the Los Alamos National Laboratory, who tested our composite materials, came to an unambiguous conclusion: the Cu-Nb wire exceeds in all characteristics the world analogs. Besides, a pulse magnetic system with a record high induction of magnetic field 85 T was already created from this wire at the University of Florida. The start-up of a 90 T supersystem in Los Alamos will be the next step.

 
стр. 48

 

The market perspectives of the innovative product are immense. Electrical engineering makes use of wires for equipment with a high magnetic field intensity (from 50 to 100 T). Used as inductors they increase the capacity twofold and, as a consequence, efficiency of equipment in implementing the magnetic-pulse method of pressing of serial details of complex form and welding of different materials in mechanical engineering, in particular, in car and aviation industries. In electronic and telecommunication technology they will contribute to reduction of weight and sizes of miniature items and conservation of their lifetime at the expense of a high indicator of "bend-twist" criterion. In aviation and space industries they will improve reliability of avionics (electron systems in aviation) due to the reduction of the mass of connecting cables. In robotic engineering they will increase stability of equipment for power transmission to operating mechanisms owing to their high resistance to bending stresses. Considerable benefits are connected with application of composite wires for organization of high-speed railway and urban trolley-bus transport, whose contact systems require frequent replacement due to increased requirements to mechanical strength, wear and corrosion resistance. According to the developers, their application in equipment of resonant power transmission has no alternative at all.

 

Science in Russia, No.2, 2012

 
стр. 49

 

By expert estimates, in the main market segment, i.e. production of electrical wires, supercomposite can compete successfully with analogs based on complex alloyed bronze, widely spread in the market, as being close to them by strength, it has twice greater conductivity.

 

Novelty of the new design was confirmed by patents of the Russian Federation and diplomas of international and national exhibitions. In 2005, it won the Contest of Russian Innovations, and in 2006 it was recognized best at the Rosatom Innovation Forum in the category of Electronics and Electrical Engineering. Today the project enters a new phase: in August 2011, the Rusnano open joint stock company and the High-Technology Research Institute of Inorganic Materials named after A. Bochvar (since 2009 it is a part of the TVEL company supplying fuel to the national nuclear power complex) signed an investment agreement for industrial production of superhigh strength nanostructured wires within the framework of the Nanoelectro joint research and production venture.

 

As Sergei Sudyev, director general of the new company, pointed out in his interview to the Atompressa newspaper (No. 41, 2011), the project is very topical: it will preserve the scientific and technical potential accumulated in the field of composite conducting materials, satisfy the growing demand in the electrotechnical market for windings of superhigh strength and electrical conductivity, and achieve an adequate position there in the perspective.

 

According to expert judgments, by 2015 the world market of superwires will reach $696 mln, which will twice exceed the level of 2009. Sudyev noted in the above publication: "The segment of wires of over 800 M Pa strength, to which a major part of our products relates, made up approximately 27 percent of the market as of 2009, and it will approach 50 percent by 2015." The Russian market of this product is modest yet: $12 mln in 2009 and $34 mln by 2015, which makes up 5 percent of the world indicator. However, according to the marketing analysis, after commissioning of national production, our country can hold 15 percent of the cable market.

 

The main part of the project financing (450 mln rubles) is provided by the Rusnano open joint stock company. The Bochvar Institute invested 570 mln rubles, mainly in the form of its intellectual property and equipment. By the end of 2014, almost 50 t of nanostructured wires will be manufactured annually in the territory of the institute, which includes two shops with high-power presses, large melting furnaces and other industrial equipment. The perspective (2014-2017) plans are connected with organization of a large-scale commercial production of the said materials at the Chepetsk Mechanical Plant (Glazov, Udmurtia), a major enterprise of the Ural Region, which produces products based on zirconium alloys, natural and depleted uranium, calcium metal and its compounds. Substantial production capacities will be released from 2014 at the plant under the program of diversification (reorientation of market outlets) of superconducting material production for ITER. But they will be put to their proper use, namely, for production of four main types of nanowires with the output of 200 t annually, which have the most solvent demand in the market.

Опубликовано на Порталусе 01 октября 2021 года

Новинки на Порталусе:

Сегодня в трендах top-5


Ваше мнение?




О Порталусе Рейтинг Каталог Авторам Реклама