OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 2 2025 temperature and a voltage of 26 V. SEM studies were carried out using a FEI Nova NanoSEM 450 scanning electron microscope equipped with an EDAX Hikari electron backscatter diffraction (EBSD) camera. EBSD analysis was performed with a scanning step of 100 nm. For subsequent texture evaluation, only results with a confidence index (CI) of more than 0.1 were used, which improved the quality of the EBSD analysis results. TEM studies were conducted using a JEOL JEM-2100 microscope at an accelerating voltage of 200 kV. Vickers microhardness was determined using a Wolpert 402MVD hardness tester using a diamond pyramid with an angle of 136° at the apex. The tests were carried out in the cross section of the rods along two mutually perpendicular diameters. The indentation step was calculated for each diameter separately, taking into account 70 measurements per diameter. The load applied to the indenter was 200 g with an indentation time of 15 s. The results of microhardness measurements obtained along two mutually perpendicular diameters in the cross-section of the specimen were averaged. Tensile tests were carried out at room temperature and a strain rate of 1×10−3 s−1 using an Instron 5882 electromechanical testing machine. Specimens were cut from the center and subsurface layers of the rod in the axial direction. The dimensions of the gauge of the specimen were 6×3×1.5 mm3. Mechanical properties (yield strength, ultimate tensile strength, elongation to failure) were determined according to GOST 1497-23. The elongation of specimens during testing was measured using the VIC-3D system. For this purpose, one of the side surfaces of the specimens was first coated with white paint, followed by the application of small drops of black paint. The VIC 2D program was used to process the obtained data. At least two specimens were tested at each point. Results and discussion Austenitization of Fe-21Mn-6Al-1C steel produced a fully austenitic, face-centered cubic (FCC) structure (Fig. 1, a). The microstructure, phase, and chemical composition were uniform across the cross section of the rod. The average size of austenite grains was 150 µm (Fig. 1, b), but annealing twins further fragmented the grains, reducing the average distance between high-angle grain boundaries to 55 µm. The fraction of twinned boundaries (Σ3) did not exceed 34 %. The direct and reverse pole figures show a weak two-component axial texture <111>// rod axis (RA) and <100>//RA (Fig. 1, c and d). The results of the study of the microstructure evolution during the CRF process are shown in Fig. 2. 20 % CRF causes microbanding along various systems. It should be noted that in the direction from the center to the edge, the deformation microbands become more pronounced (Fig. 2, a1 and a2). According to diffraction c a b d Fig. 1. X-ray diffraction pattern (a), grain misorientation map (b), direct pole figure (c), and inverse pole figure (d) of the Fe-21Mn-6Al-1C steel in the initial state c
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