Simulation of dynamic channel-angular pressing of copper samples with allowance for experimental data of loading

D. V. Yanov ; A. S. Bodrov ; N. V. Pakhnutova ; S. A. Zelepugin

Vestnik Tomskogo gosudarstvennogo universiteta. Matematika i mehanika, no. 60 (2019), pp. 141-151

Résumé

One of the urgent problems in the field of materials science is producing of metals and alloys with an ultrafine-grained (UFG) structure. Metals with UFG structure are characterized by improved physical and mechanical properties, such as increased strength, cold brittleness, and radiation stability. This paper considers a method of dynamic channel-angular pressing (DCAP) which is used to obtain the UFG structure. The purpose of this work is to simulate numerically the DCAP process of a copper sample using experimental data of loading. The experimental data available in the scientific literature have been analyzed to specify the initial conditions as follows: the pressure acting on the rear part of the sample is $P_0=310$ MPa and the initial velocity of the sample can be varied in a wide range. Numerical simulation is performed using a modified finite element method within the framework of elastoplastic model of a damaged medium. The numerical computations have shown that the copper sample successfully undergoes the DCAP process at the following initial parameters: $v_0 = 170$ m/s and $P_0 = 310$ MPa. Almost the entire sample is exposed to uniform intense plastic deformations, except for the front and rear parts. Also, a slight elongation of the sample occurs along the longitudinal axis, and the temperature rises up to $600$ K in the contact region of the sample with the walls of the horizontal part of the channel.

Détail

Keywords: severe plastic deformation, dynamic channel-angular pressing, finite element method.