OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 3 2025 To prepare larger fractions, WC powder (TU 6-09-03-360-78) with particle size of 1 ≤ WC ≤ 40 μm was used, which was separated through 40 μm and 20 μm sieves using a vibrating table. The particle diameter of the powders was measured using the arbitrary secant method according to ASTM E112-12. The average particle size of aluminum and nickel powders was 18.0±10.3 µm and 11.3±6.4 µm, respectively (Fig. 1, c). X-ray diffraction (XRD) patterns revealed that as the WC particle diameter decreased, a monotonic decrease in reflection intensity and an increase in reflection width were observed, consistent with the Scherrer equation (Fig. 1, g). The substrate (cathode), made of grade 45 steel in the form of a cylinder (d = 12 mm and h = 10 mm), was immersed in a mixture of granules and powders with the end surface facing down. Thus, the coating was formed on the end and side surfaces of the substrate, with a total covered area of 2.88 cm2. An IMES40 generator was used as a source of current pulses. The device settings were as follows: pulse duration – 100×10−6 s, frequency – 103 Hz, pulse current amplitude – 170 A at an open circuit voltage of 25 V. Ta b l e 1 Composition of non-localized electrode and coating designations Designation of coatings Proportion of granules, vol.% Proportion of Al powder, vol.% Proportion of Ni powder, vol.% Proportion of WC powder, vol.% WC powder fraction, µm WСn 93.80 2.05 1.35 2.80 0.08 ≤ WC ≤ 0.1 WС20 1 ≤ WC ≤ 20 WС40 20 ≤ WC ≤ 40 a b c d Fig. 1. SEM image of WCn fraction powder particles (a) and the results of its BET analysis (b); integral distribution of Ni, Al, WC20, WC40 powders (c) and X-ray diffraction patterns of WC powders (d)
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