OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 The 3D model allowed us to estimate the distribution of the strain over the cross-section of the pressed bars near the deformation zone (fig. 9, a, b). It is established that when the die channel axes are arranged along the axis of the rectangular groove (fig. 9, a), non-uniformity of strain distribution is not observed over the cross-section of the central bar. However, the pressed bars from the first and the third channels exhibit non-uniformity, with a larger degree of strain being on the peripheral part of the bars on the side bordering the center one. This difference in the strain degree reaches 20 %. This non-uniform strain distribution can be explained by the positioning of the axes of the channels. The axis of the center channel is positioned along the radius of the container, while the axes of the first and third channels are offset from the radius line out of necessity. This is what creates a non-uniform effect on bars. When the axes of the channels are arranged along the container radius, this non-uniformity is reduced to 12 %. а b Fig. 9. Distribution of the strain in the steady stage of the angular pressing process in the cross section of the pressed bars in the XZ plane with the arrangement of the die channels along the axis of the rectangular groove (a) and along the radius of the container (b) Conclusions 1. The structural diagramm of the device for angular multichannel pressing and particular features of the die are described. The device offers a wide range of manufacturing options due to the use of the die that allows to change the shape of the pressed product in cross-section into the shape given by the die opening. As a result, it is possible to produce bars of round, square and other sections. 2. The paper is focused on two variants of manufacturing magnesium bars with a diameter of d = 4.1 mm and a number of die channels n = 3 using the method of multichannel angular pressing. The first variant involves the die with its channel axes positioned along the axis of the rectangular groove, and the second variant involves the die with its channel axes positioned along the radius of the container. Computer simulation of these variants of the process is carried out with the DEFORM-3D software package. 3. The mean stress evaluation in the three-dimensional representation made it possible to establish that in both process variants, the cylindrical blank during deformation is under compressive stresses at the
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