OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 25 No. 3 2023 The wear resistance characteristics obtained are associated with a change in the structural and phase state of the coatings formed by appending different amounts of hardening particles. An analysis of the friction surface of the coating obtained without appending reinforcing particles revealed that during testing, the material was plastically displaced from the friction zone to the periphery (fig. 10a). A similar character of the wear crater structure was observed in coatings containing 5 and 10 % CrB (fig. 10b). An increase in the amount of borides to 20 %, accompanied by an increase in microhardness, contributed to a decrease in plastic deformation. As a result, the material displacement was not observed on the friction surface (fig. 10c). An additional factor that prevents severe plastic deformation of the coating material is assumed to be the formation of a skeleton eutectic. As mentioned above, this type of eutectic connects separate primary borides and forms a spatial network. The study of friction surfaces by scanning electron microscopy revealed signs of the adhesive wear of the coatings. Traces of seizure, delamination, and fracture of the material were found on the surface of the coatings (fig. 10d, f). These features are the mostly noticeable on the surface of the coating without hardening particles. Ta b l e 4 Average values of the friction coefficients and the worn material volumes No. Composition Friction coefficient Average value of worn material, mm3 1 CoCrFeNiMn 0.71i ± 0.22 0.61 ± 0.1 2 CoCrFeNiMn : CrB 95:5 0.73 ± 0.23 1.1 ± 0.09 3 CoCrFeNiMn : CrB 90:10 0.68 ± 0.22 0.77 ± 0.08 4 CoCrFeNiMn : CrB 80:20 0.62 ± 0.17 0.17 ± 0.04 5 CoCrFeNiMn : CrB 70:30 0.57 ± 0.15 0.1 ± 0.04 a b c Fig. 10. Profiles of the wear grooves (a–c) and the wear surface micrographs (d–f); a – 0 % CrB; d – 0 % CrB; b – 10 % CrB; c – 20 % CrB; e – 5 % CrB; f – 30 % CrB d e f
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