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The development of a numerical model capable of simulating the forming processes characterized by additional reversible movement of tools is the subject of this paper. The major assumption of this process is the introduction of additional shear stresses into the material in order to induce the strain path change effect. The scope of the problem is very broad, so the focus in the present work is on the process of flat rolling with additional oscillatory movement of rolls along their axes. Due to the sophisticated nature of this process particular attention is paid to the reduction in computational time by minimizing the number of required finite elements. The developed model is used to study differences in material behaviour during rolling with different roll velocities. A detailed description of the developed numerical model and examples of obtained results are presented in this paper. A comparison with experimental analysis is presented, as well.

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In this study, commercial Cu was subjected to plastic deformation by compression with oscillatory torsion. Different deformation parameters were adopted to study their effects on the microstructure and mechanical properties of Cu. The deformed microstructure was characterized by using scanning electron microscopy (SEM) equipment with electron backscattered diffraction (EBSD) facility and scanning transmission electron microscopy (STEM). The mechanical properties were determined on an MTS QTest/10 machine equipped with digital image correlation. Can be found, that process performed at high compression rate and high torsion frequency is recommended for the refining grain size. The size of structure elements: average grain size (D) and subgrain size (d) reached 0.42 m and 0.30 m respectively, and the fraction of high angle boundaries was 35%, when the sample was deformed at a torsion frequency f= 1.6 Hz and compression rate v=0.04 mm/s. Deformation at these parameters leads to an improvement in strength properties. The strength properties are about two times greater than the initial state.