National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow, Russia:

M. G. Isaenkova, Professor, e-mail: isamarg@mail.ru
Yu. A. Perlovich, Leading Researcher
Soe San Thu, Post-Graduate Student
O. A. Krymskaya, Assistant
V. A. Fesenko, Senior Researcher

This paper shows the research of peculiarities of the processes of Zr monocrystals reorientation during their rolling and following recrystallization. Use of monocrystals with different orientation relatively to outer directions of rolled plate allows to observe the reorientation of basal normals in the case of twinning and/or slip activization. The obtained results confirm and define the previously observed regularities of texture formation in pure Zr and its alloys, consisting of three stages of rolling texture development and consecutive activization of deformation mechanisms. The diagram of predominant plastic deformation mechanisms, calculated for α-Zr rolling, is not valid for all crystal orientations. Compression can activate twinning within regions of basal and prismatic slip operation. Under the monocrystal rolling, the twinning is capable to provide the formation of components, dominating in α-Zr texture at all further stages of texture development. However, at the same time, this twinning is accompanied by the slip, responsible for the level of strain hardening, sufficient for recrystallization. There were revealed the regularities of new grains growth during the subsequent recrystallization, entirely determinated by deformation mechanisms, operated at rolling stage. Regions of α-Zr matrix, deformed with predominant participation of twinning, are characterized by a decreased tendency to recrystallization. During the recrystallization in α-Zr there is implemented the mechanism of predominant growth of regions with maximum deformation hardening, corresponding by their orientation to the slopes of rolling texture maximal.

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