Institute of Chemistry (Far Eastern Branch of Russian Academy of Sciences), Vladivostok, Russia:

D. V. Mashtalyar, Senior Researcher of Laboratory of Biomedical Composite Coatings, e-mail: madiva@inbox.ru
S. L. Sinebryukhov, Assistant Professor, Head of Laboratory of Non-Stationary Surface Processes
I. M. Imshinetskiy, Junior Researcher of Laboratory of Biomedical Composite Coatings
S. V. Gnedenkov, Professor, Deputy Director for Science, Head of Department of Electrochemical Systems and Surface Modification Processes

Magnesium alloys are widely used in modern technology, primarily due to its low density, which can significantly reduce the weight of products and structures. The main drawbacks limiting widespread use of magnesium alloys is their high corrosion activity and low wear resistance. Formation of protective multifunctional coatings on magnesium alloy using the method of plasma electrolytic oxidation (PEO) in electrolytic system containing nanosized particles of titanium nitride was investigated. Using the developed electrolyte system allowed for intensive introduction of nanoscale powders in the coating. Electrochemical and mechanical properties of obtained heterooxide layers were examined. Anticorrosion properties of PEO-layers, containing titanium nitride nanoparticles, are less pronounced than the base PEO-coatings, but higher than for pure magnesium MA8. Sclerometry and tribology studied adhesion properties and wear coatings. The adhesive force characterized by a critical load at which delamination layer PEO-containing nanosized particles of titanium nitride, is 25% higher than for the PEO coating formed without nanoparticles. The wear resistance of the coating with nanoparticles increases 2.2-fold, as compared to respective values for the PEO coating formed in the base electrolyte. These data showed that modification of titanium nitride nanoparticles into the coatings composition significantly improves their mechanical properties, with almost no corrosion deteriorate.

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