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

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.