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Machines operating in aqueous environments may be subjected to cavitation damage during operation. This study aims to evaluate the cavitation resistance of WC-10Co4Cr and WC-20CrC-7Ni coatings under cavitation erosion conditions with additional electrochemical effects. The coatings were deposited on AISI 1040 steel substrates using a high velocity air fuel thermal spray process. The microstructure of the coatings was observed by a scanning electron microscope, while their phase composition was analyzed using an energy-dispersive microanalysis system. In addition, the microhardness of the coatings and substrate was measured, and the surface topography of the eroded surface layers was observed using a 3D optical profilometer. The results revealed that the cavitation resistance of the WC-20CrC-7Ni coatings was better than that of the WC-10Co4Cr coatings. The observation of the structure and surface topography made it possible to identity the reasons for the differences between the cavitation resistance of both coatings: The WC-20CrC-7Ni coatings had a finer grain structure, lower pore density, and lower as-sprayed surface roughness. These differences, along with the presence of a high Cr and Ni content in the feedstock powder, that increased the coating corrosion resistance, contributed to improving the cavitation resistance and reducing the material loss of the WC-20CrC-7Ni coatings. © 2021, ASM International.

FIELD: metallurgy. SUBSTANCE: invention can be used to produce welded joints from medium-carbon medium-alloyed armour steels. Welding wire contains components in the following ratio, wt. %: chromium 18.5–22.0, carbon 0.3–0.4, nitrogen 0.1–0.2, aluminium 0.05–0.1, titanium 0.08–0.2, iron - the rest. EFFECT: welding wire provides high bullet resistance of welded joints., Изобретение может быть использовано для получения сварных соединений из среднеуглеродистых среднелегированных броневых сталей. Сварочная проволока содержит компоненты в следующем соотношении, мас. %: хром 18,5-22,0, углерод 0,3-0,4, азот 0,1-0,2, алюминий 0,05-0,1, титан 0,08-0,2, железо – остальное. Сварочная проволока обеспечивает высокую пулестойкость сварных соединений.