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In this study the kinetic curves of cavitation wear of cast steels 20 GL and 30 L used for production of critical elements of hydraulic machines were obtained. The typical predominance of growth rate of cavitation mark diameter over its depth was found on the surfaces of the investigated cast steels. The revealed phenomenon made it possible to offer a formula for estimating the volume removal of the examined cast steels in order to expand the scope of the method according to ASTM G134-17. This method uses profilometry and microscopy and allows to determine cavitation resistance both for homogeneous and heterogeneous materials, including materials after modification of their surface (with different types of coatings and hardenings).

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The paper presents the results of experimental studies to determine the effect of surface treatment of galvanized steel using laser equipment on wettability properties and corrosion resistance. It is shown that laser texturing of the roughness on the zinc layer contributes to the achievement of the hydrophobic state. It is noted that during ablation and discontinuity of the zinc layer on the steel surface, the hydrophobic state is achieved only due to the formation of molecular layers of the surfactant. An increase in the corrosion resistance of galvanized steel was achieved by activating the zinc layer due to laser texturing of the surface at a radiation density of 20 and 35 J/cm2. With ablation and discontinuity of the zinc layer on the steel surface, the corrosion resistance is significantly reduced.

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