OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 3 2025 and AlFe, the reflections of which overlap on the 2θ scale. The W2C phase formed as a result of tungsten carbide decarburization during interaction with molten iron in a melt pool, according to reaction 1: 2WC + 3Fe = W2C + Fe3C (1) Thus, the prepared coatings exhibit a metalloceramic structure, where the metal binder is composed of aluminides and ferronickel, while tungsten carbides serve as reinforcing phases. The X-ray diffraction patterns of coatings obtained using micron-sized powders differ significantly from those obtained using nanopowders. Specifically, tungsten carbide (WC) is the most abundant phase in the WC20 and WC40 coatings, whereas ferronickel and the Al86Fe14 aluminide are present in higher concentrations in the WCn coating (Table 2). Furthermore, the concentration of the W2C phase is lowest in the WCn coating compared to the other samples. a b Fig. 2. Mass transfer of samples during coating deposition (a) and XRD analysis of the obtained coatings (b) Ta b l e 2 Results of semi-quantitative phase analysis of coatings in accordance with Fig. 2, b Samples Concentration, vol.% WC BCC W2C FeNi Al86Fe14 WCn 19.5 20.5 3.9 40 16.1 WC20 32.3 23.6 20.9 15.6 7.5 WC40 31.0 28.4 30.0 6.4 4.6 Cross-sectional images of the MMCs coatings are shown in Fig. 3, a–d. The average coating thickness was very similar, ranging from 24.3 to 26.1 µm. The coating structure consists of a Fe-Ni-Al matrix and grains in the micron and submicron ranges. The Wn coating appears homogeneous without micron-sized inclusions (Fig. 3, a). At higher magnification, diamond-shaped crystallites with sizes ranging from 0.16 to 0.47 µm are observed in the Wn coating, uniformly distributed throughout the coating layer (Fig. 3, b). Given the low concentration of the W2C phase in this coating (Fig. 2, b), it is reasonable to assume that the diamond-shaped crystallites are tungsten carbide. In the W20 and W40 coatings, both micron- and submicron-sized carbide grains are observed. Elemental mapping results reveal that the micron-sized inclusions are enriched in tungsten and carbon (Fig. 4). The difference in size and non-uniform distribution
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