Institute of Material Science and Metallurgy of Ural Federal University named after the first president of Russia B. N. Yeltsin, Ekaterinburg, Russia

Yu. N. Loginov, Professor, e-mail: unl@mtf.ustu.ru
S. L. Demakov, Professor
A. G. Illarionov, Assistant Professor
M. A. Ivanova, Post-Graduate Student

Ural Mining and Metallurgical Company, “JV “Katur-Invest” JSC, Verkhnyaya Pyshma, Sverdlovsk Oblast, Russia

V. A. Romanov, Head of Production and Technical Department

The object of research is definition of the homogeneity degree of structure and properties of copper wire rod, which was manufactured by the continuous casting and rolling method during the CONTIROD process. At the same time, there were solved the tasks of structure description and determination of physical and mechanical properties of electrotechnical copper. Durometer researches were carried out along with application of metallographic research methods, including optical microscopy and electronic microscopy with usage of diffraction of back-scattered electrons. Methods of textural analysis were also applied. Metallographic method confirmed the fact of existence of oxygen part in the form of particles of oxides, which can look like line allocations. There is defined that the size of grain increases from the center to the periphery. According to this, the radius averaged value is 17 μm. There is established that the maximum of the frequency characteristic of the grain size is constantly falling at the range of 10–15 mkm. Increasing of average grain size to the periphery occurs not at the expense of volume coarsening of grains, but at the expense of appearance of groups of significantly larger grains (50 mkm and above) on the periphery. At the same time, the structure heterogeneity centers arise on the wire rod periphery. However, these centers are absent in the preparation center. The weak texture of metal is defined. Texture of the central zone of semi-finished product is presented by lowdefined recrystallization texture, which repeats the rolling texture {110} <112>. Average Vickers hardness is 71 HV, and elasticity module is 111.7 GPA. There is defined the increased dispersion of hardness, which is connected with a composite structure of material, according to the presence of copper oxide particles in it. There is also defined the statistically significant asymmetry of distribution of hardness, relatively to the vertical axis of wire rod. This phenomena is explained by irregular outflow of heat during the process of metal crystallization on the foundry installation, which leads to various rate of cooling and formation of various structure of metal. Manufacturing of products from electrotechnical appointment copper is the results application area. There is made a conclusion about the possibility of structure alignment due to the management of uniformity of thermal fields at continuous casting.

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