Tula State University, Tula, Russia:

A. A. Pasynkov, Assistant Professor of a Chair “Mechanics of Plastic Form Change”
O. I. Boriskin, Professor, Director of Polytechnic Institute
S. N. Larin, Professor, Assistant Professor of a Chair “Mechanics of Plastic Form Change”, e-mail: mpf–tula@rambler.ru

The processes of isothermal deformation at a small deformation speed open up a wide range of possibilities to manufacture responsible-usage products from difficult-to-form alloys. The question of theoretical feasibility of the process of distribution of pipe billets with thin walls and high coefficients of distribution from difficult-to-form alloys is relevant these days. However, regardless of sufficient number of works, dedicated to research of the process, the question of theory of deformation of high-quality products from difficult-to-form alloys in the regime of short-term creep has not been assessed enough. The article presents the research results of the process of distribution of pipe billets in isothermal conditions, based on analytical methods such as mathematical and computer modelling as well as experimental research. It determines the optimal form and sizes of the instrument, which guarantee the best quality parameters of the obtained parts and the minimal force of deformation.
Our invstigation results are published with the sponsorship of the supporting institute Tula State University.

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