National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow, Russia:
M. G. Isaenkova, Professor
O. A. Krymskaya, Assistant, e-mail: olgakrym@inbox.ru
Yu. A. Perlovich, Leading Researcher
S. S. Pakhomov, Senior Engineer

This article is devoted to determination of correlation between crystallographic texture of Zr-based alloy products and anisotropy of their yield stresses. In the context of this research, the calculation of macroscopic anisotropy of yield stresses of Zr alloys was carried out on the basis of their crystallographic texture data. In order to compare the experimental and calculated anisotropy of Zr – 1% Nb alloy products, the samples, cut out from rolled slabs in the rolling direction, transverse and normal directions, were stretched and compressed to various deformation degrees. Some incomplete direct pole figures of samples before and after deformation were observed by X-ray diffractometry method for investigation of change of crystallographic texture. These figures were used for estimation of texture change as a result of samples' tension or compression in different directions. Normalized yield stresses were calculated for three orthogonal directions of the studied samples, using texture data. The calculated values, obtained by such method, were compared with the values, experimentally measured by initial loading curves. Tensile and compressive mechanical tests are connected with changes of their initial textures, which behavior depends on the direction of applied loading and on the type of activated deformation mechanisms. Changes in the sample texture inevitably lead to changes in its properties' anisotropy. The given data testify that product anisotropy is increased under uniaxial tension and compression, in case of a coincidence of loading directions in the time of testing and previous deformation treatment. At the same time, when these loading directions are mutually opposite, anisotropy is gradually decreased with growing of deformation degree and can be even changed into reverse one.

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