Corresponding member of the RAS Romanov Evgeny Pavlovich

Romanov Evgeny Pavlovich, an Associate Member of the Russian Academy of Sciences, a Doctor of Physics and Mathematics, Professor is a leading expert in the field of materials science, physical chemistry and composite materials technology, precision metallurgy of alloys, steels and intermetallic compounds, growth of single crystals. E.P. Romanov’s scientific school of thought has made a lot of works on the synthesis and study of the structure and properties of various intermetallic compounds (A15, C15, etc.), magnetic alloys. Also, E.P. Romanov and his colleagues have investigated the radiation effect on the structure of superconductors; grown single crystals of refractory metals of the highest degree of purity and perfection; developed fractal approach to the analysis of structural transformations and kinetic phenomena in solids and a glass-ceramic method of forming elongated high-temperature superconductivity products. For a long time, P.E. Romanov, with his staff, had been involved in obtaining heat-resistant materials by melting in the poly- and monocrystalline state; studied the effect of alloying and modifying additives on their structure and properties. The above alloys include nickel-based superalloys, Ti3Al and TiAl compounds. As far back as 1976 and 1978, undertaking practical training in Germany, E.P. Romanov was the first to formulate an idea of creating natural fiber-containing superconducting composites (Cu-Nb, Cu-Sn-Nb) by rapid directional solidification combined with plastic deformation and diffusion annealing.

His first works dealt with the preparation and study of alloys of beryllium with doping additives, as well as of an In-Mg electrical alloy. An interesting fact is that the alloy, when utilized, gives the growth to metallic “whiskers” to be contacts, with the whiskers strength being close to theoretical. In the early 1960s, when the study of Ti-Nb, Zr-Nb alloys with high superconducting properties began booming, E.P. Romanov and his colleagues directed their efforts to investigate their fine structure and superconducting properties. During these years, they proposed and thoroughly examined the Zr-4 wt. % Nb model alloy. It was found that the alloy, being heat-treated, forms chains of an almost pure superconductor (niobium) along boundaries of martensite needles. Also, the alloy hardly changes its structure and superconducting properties under varying treatment conditions. It was then that the filamentary model of hard superconductors received experimental confirmation. This caused great interest and approval of the scientific community of our country.

In 1975, E.P. Romanov’s group began to work together with the A.A. Bochvar HighTechnology Scientific Research Institute of Inorganic Materials (HTSRIIM), Moscow. In our country, the Institute mentioned above was the main developer of superconducting materials (Nb-Ti, Cu-Sn/Nb3Sn) at that time. Joint work with this Institute had been lasting for over three decades to be a scientific basis to manufacture superconducting materials for industry. The results of this collaboration are:

• Obtaining of free bronzes with high tin content, needed to create Cu-Sn/Nb composites.
• The establishment and elimination of the causes of the very high fragility of the free bronzes.
• The determination of features of plastic deformation in the bronzes under composite conditions, as well as regimes of the deformation to increase the plasticity of the bronzes in composites.
• The elucidation of the mechanism of formation of the Nb3Sn, V3Ga superconducting layers by electron microscopy studies of the structure of Cu-Sn/Nb, Cu-Ga/V composites.
• The improvement of structure and superconducting properties of composite diffusion layers by a newly proposed two-step annealing. The novelty is confirmed by a patent. The annealing is still used today.

Over time, it has become necessary to use Nb3Sn-based composites in high magnetic fields (20 Tesla and above). It has turned out that this can only be achieved by doping with various additives. In this regard, a whole new direction has appeared to study the mechanism of the effect of various additives on structure and superconducting properties of composites. As a result, the most alloying elements (Ti and Ta) have been found.

In this regards, developed in HTSRIIM, high-strength Cu-Nb nanocomposites with high electrical conductivity have required separate examination. As a result, it has been found that Nb-fibers of the wire samples possess a special planar texture responsible for unusual properties of these materials. Through close contact with HTSRIIM, the data have been used to timely adjust the technology of producing superconducting and high-strength Cu-Nb composites. In 2008, Russia joined the project of building the international fusion reactor as a supplier of superconducting Nb3Sn-based composites. This is a considerable contribution of the team led by E.P. Romanov to the implementation of this project. At once, after the discovery of hightemperature superconductivity (1987), E.P. Romanov, with his staff, took part in the research of high-temperature superconducting materials. First, they studied Y-Ba-Cu-O ceramics, afterwards - a Bi-, Pb-2223-based ceramic composites with high superconductive properties (jointly with HTSRIIM). Through a comparative investigation of the fine structure and superconducting properties, Romanov’s group has identified structural elements, negatively and positively affecting the critical current. Cooperative efforts of IMP and the Moscow State University have resulted in finding features of the structure of thin film Y-Ba-Cu-O-based composites of the second generation. The latter provide the critical current density in the films by two orders of magnitude larger than in single crystals. These works have showed how the stability of the deposited films and bulk Y-Ba-Cu-O-based samples is affected by the environment, atmosphere, oxygen content and low-temperature annealing. The causes of instability and structure changes accompanying it have also been revealed.

Currently E.P. Romanov is the guiding hand of a trend related to the creation of high-density MgB2 superconductors and composites based on them.

E.P. Romanov was born on July 1, 1937 in the city of Przhevalsk Kirghiz SSR. In 1959, after graduating from the Faculty of Metallurgy of the Ural Polytechnic Institute named after S.M. Kirov, E.P. Romanov began working at the Institute of Metal Physics, Academy of Sciences of the USSR. In 1987 he became a head of the Department of Precision Metallurgy and the Laboratory of Intermetallic Compounds and Single Crystals. In 1986 he was offered the post of Chief Scientific Secretary of the newly created Ural Branch of the USSR Academy of Sciences (since 1990 – the Russian Academy of Sciences). In this position, he had been working for more than twenty years. Evgeny Pavlovich is known as a major organizer of science. In his capacity of the Chief Scientific Secretary, he devoted much energy to establishment of a number of institutes and research centers in cities such as Perm, Orenburg, Izhevsk, Syktyvkar, and others. For more than fifteen years, E.P. Romanov had been a scientific secretary of the Scientific Committee, an executive director and a member of the board of trustees of the International Demidov Fund. E.P. Romanov is an author of over 300 scientific papers. He has supervised 1 Doctor and 10 Candidates of Sciences, with five candidates and the Doctor defending superconducting themes. At the Ural State University named after A.M. Gorky, for 35 years, E.P. Romanov had been delivering lectures on condensed matter physics and methods for producing crystals and especially pure substances. In 1996 he was awarded the honorary title of “Honored Worker of Science”. Currently, he is an academic adviser to the Department of Precision Metallurgy of IMP UB RAS.