OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 1 2025 4. The phase composition and fine structure of the implanted layer were determined, the phases formed as a result of implantation were identified, and an analysis of changes in the average dislocation density and the size of mosaic blocks was performed. Methods and materials Microstructural analysis of the experimental cast iron The microstructure of implanted grey cast iron (type CI20 pearlitic structure, chemical composition is shown in Table 1) was analyzed using a Stereoscan S-180 scanning electron microscope with resolution up to 60 Å on 10×10×10 mm samples (Fig. 1) after etching in 3 % HNO3. The samples were cut in a direction perpendicular to the implanted layer and examined at magnifications of ×2,900, 5,000. Ta b l e 1 The composition of cast iron Element С Si Мn Сr Р S Percentage content, % 3.45 2.2 0.8 0.32 0.1 0.12 Fig. 1. Gray cast iron sample diagram Microdurometry analysis of cast iron after implantation For microdurometry studies, samples obtained using three different treatment modes were used (with doses of 1017, 2×1017 and 5×1017 ions/cm2 and with implantation energy of 40 KeV). The studies were carried out on the Neophot-2 metallographic microscope equipped with an attachment for measuring microhardness (with a load of 10 g). Microhardness was measured in the direction from the implanted surface to the centre on samples cut perpendicular to the implanted layer. Microhardness values along the depth of the layer were determined as the arithmetic mean of 5 measurements. Phase Composition Analysis of the Cast Iron Surface after Implantation X-ray diffraction studies were conducted using a DRON-3 diffractometer. X-ray analysis was carried out using Co Kα radiation. It is known that the implanted layer itself has a thickness of only about 1,000 Å [26–28]. In addition to specifically applicable imaging devices, the phase analysis was facilitated by the fact that the most intense lines of the phases expected in the implanted layers (nitrides, carbides, etc.) are located in the range of small reflection angles. Due to the geometry of imaging at small angles X-rays travel a longer path in the surface layer than at angles close to 90°, thereby increasing the reflecting volume of the phases formed. Despite the fact that the intensity of the diffraction lines of the phases in the implanted layers is many times lower than the intensity of the matrix lines, it was possible to identify the phases.
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