OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology In order to verify the feasibility of angular pressing according to the proposed technique, two models of this process were built with the use of a die with the number of channels n = 3 and obtaining bars with a diameter d = 4.1 mm in the DEFORM 3D software package. Fig. 2 shows two variants of the die design. The axes of the channels in both variants are at an angle of 90° relative to the container axis, however, in the first variant, the axes of the channels are located along the axis of the rectangular groove (fig. 2, b), and in the second variant, the axes of the channels are located along the radius of the container (fig. 2, c). For a more uniform metal flow from the die channels, it is recommended to have it placed at the same distance from each other. а b c Fig. 2. The configuration of the die with a number of channels n = 3 for angular pressing of bars with a diameter d = 4.1 mm (a); the 1st variant of a die section (the axes of the channels are located along the axis of the rectangular groove) (b); the 2nd variant of a die section (the axes of the channels are located along the radius of the container) (c) Magnesium of grade Mg90 (GOST 804–93) was selected as a low-ductile metal of the blank. Magnesium is a metal with high specific strength, low density, high damping performance, biocompatibility, biodegradability, as well as chemical activity. These properties make it popular for the use in rocket and space equipment, aviation, automotive, medical and the oil industry [18–21]. Magnesium, as a material with a hexagonal close-packed (HCP) lattice, has a limited number of slip planes, which leads to its reduced ductility at room temperature [22–23]. However, hot deformation of magnesium, which increases the level of plastic properties [24], has disadvantages: oxidation of the surface of semi-finished products due to low corrosion resistance of magnesium, gas trapping within the metal volume [25], loss of the metal strain hardening effect, which allows increasing strength properties the final product, as well as an increase in energy costs for heating the blanks. Therefore, the possible approach is to carry out the processing in a cold state and to increase the ductility, for example, by increasing the level of compressive stresses [26–27]. It also means that a comprehensive compression scheme is implemented, in which compression stresses act along all three axes of the coordinate system. This is exactly the pattern that occurs in pressing processes.
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