Tula State University, Tula, Russia:

A. A. Pasynkov, Assistant Professor, Department of Mechanics of Plastic Form Change, e-mail: sulee@mail.ru
S. N. Larin, Assistant Professor, Head of the Department of Mechanics of Plastic Form Change, e-mail: mpf-tula@rambler.ru

National University of Science and Technology “MISIS”, Moscow, Russia:
G. A. Nuzhdin, Learning and Research Center of Management Systems and Certification

Production in the form of hollow cylinders of various sizes with a constant wall thickness and a reach-through hole in the bottom are very common in engineering industry. Manufacturing of such goods is most efficient through various non-cutting shaping processes, among them a reverse extrusion, especially when the part is subject to increased requirements due to the specificity of application of these products. In this connection, manufacturing of the parts by extrusion looks preferable in view of the favorable deflected mode, continuity and microstructure, which are being formed during the deformation process. Since it is believed that the article is to meet the stringent requirements for strength and weight, non-ferrous alloys marked by strength are used for its production. Therefore, the question of selecting the technology modes is very pressing. To select a rational scheme of extrusion in the view of minimal forces, stresses in the product and achieving maximum degrees of deformation, a finite element modeling of the process was performed. It is assumed that the forgings is made of AA5083 aluminium alloy. Various modes of the tube and bar stocks extrusion were considered. In particular, various temperature and speed conditions of deformation have been considered: cold volumetric deformation, hot volumetric deformation, isothermal deformation. Different process schemes were compared based on the formed deflected mode, minimal force parameters, as well as on the formation of lower stresses in the tool to ensure its durability. The obtained results can be useful as recommendations for choosing a variant of manufacturing technology for products and semi-finished products that are similar in configuration.

This work was supported by grant NSh-2601.2020.8 (НШ-2601.2020.8).

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