Institute of Metal Physics named after M. N. Mikheev UrB RAS, Yekaterinburg, Russia

B. I. Kamenetskii, Leading Researcher of the Strength Laboratory

FGAOU VO “Ural Federal University named after the first President of Russia B. N. Yeltsin”, Yekaterinburg, Russia

Yu. N. Loginov, Professor of the Chair for Metal Deformation Processes, e-mail: j.n.loginov@urfu.ru

The analysis of the deformation scheme of low-plastic materials is presented, including angular pressing of a flat blank from a round billet and subsequent sheet rolling. In contrast to equal-channel angular pressing, the billet with a round cross-section is proposed as a preform with transformation of its shape into a rectangular section with a smaller area. The boundary conditions for setting the boundary value problem have been developed. The finite element method is used to calculate the deformed state. The shear deformation ratio and the strain tensor components have been also calculated. It was revealed that  there are two types of deformation for such loading scheme. One kind is caused by a change in the cross-sectional area from a larger value to a smaller one, and the second one is associated with additional shifts which are predetermined by changing the direction of metal movement inside the container. This allows to obtain a high level of deformation in general. It was revealed that the deformation ratio calculated by the finite element modeling is lower than calculated by the engineering approach which is explained by the effect of hard zones. Experiments have been carried out on pressing of as-cast magnesium having low plastic properties revealed during upsetting experiments. The use of the angular pressing scheme has enabled to achieve a relative deformation level of 96% that corresponds to the elongation ratio during rolling of 17. The punch specific pressures during pressing were 1200–1300 MPa, and the press force was 1670–1800 kN. The increase in plasticity of the deformable material is explained by the behavior of the recovery and recrystallization processes directly during the deformation. That is caused by a high level of deformation. The developed scheme for magnesium does not require the use of heating to produce sheets with a thickness of up to 10 μm.

The work was carried out with the partial financial support according to the Decree No. 211 of the Government of the Russian Federation, contract No. 02.A03.21.0006, and within the framework of the state assignment on the topic "Pressure" No.АААА-А18-118020190104-3 and project No. 18-10-2-24 of the UB RAS Program.

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