Giredmet

M. G. Lavrentev

V. B. Osvensky

TISNUM

M. V. Mezhenny

Institute for Problems of Mechanics, Russian Academy of Sciences, Moscow

A.Yu. Ishlinsky

We derive a mathematical model for the composite material extrusion process which describes the main features of the resulting material stress−strain state. The extrusion process includes extrusion of a cylindrical billet of pressed powder through a die of desired geometry. Die geometrical parameters and process speed can be preset. The computational model is based on combined elastic−plastic body approximation. The numerical technique uses a finite element approximation on Lagrangian grid, which changes over time with changes in sample shape. To perform it we use adaptive grid units generation in areas of sample high stress and strain. The calculations were performed in Crystmo/Marc software package. We study the basic features of stress−strain state of the material obtained at different stages of extrusion process.

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