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

S. V. Gnedenkov, Deputy Director, Head of Department of Electrochemical Systems and Surface Modification Processes
S. L. Sinebryukhov, Assistant Professor, Head of Unsteady Surface Process Laboratory
D. V. Mashtalyar, Senior Researcher (Laboratory of Composite Biomedical Purpose Coatings)
I. M. Imshinetskiy, Junior Researcher (Laboratory of Composite Biomedical Purpose Coatings), e-mail: igorimshin@gmail.com

Stable electrolytic complex systems were developed on the basis of suspensions, containing ZrO₂ and SiO₂ nanoparticles. These systems were used for obtaining of prospective protective nanostructured ceramics-type composite coatings on МА8 magnesium alloy, using plasma electrolytic oxidation (PEO) method. Application of developed electrolytic systems allowed to provide the intense introduction of nanosized oxide powders in coating material. Electrochemical and mechanical properties of obtained layers were researched. There was made a definition, that scalar impedance module on 0,1 Hz frequency ratio for ZrO₂ nanoparticle containing coatings is by one and a half order higher, then the one for the coatings, obtained in electrolyte without nanoparticle application. Anticorrosive properties of PEO-layers, containing SiO₂ nanoparticles, are less-expressed. Nanoparticle-containing layers are harder (in comparison with the coatings, obtained in base electrolyte). The coatings, containing ZrO₂ nanoparticles, have the best microhardness values. SiO₂ nanoparticles provide considerably small microhardness value. The surface of nanoparticle-containing coatings is rather less-porous and more dense, then the surface of coatings, obtained in electrolyte without nanoparticles. Wear of nanoparticle-containing coatings is lesser than the wear of ones, obtained without nanoparticles. Coatings with SiO₂ and ZrO₂ nanoparticles have bigger microhardness, in comparison with base PEO-layer. According to this, these coatings stand by more than 1.2–1.4 cycles until destruction, in comparison with base PEO-layer.
This work was carried out with the support of Russian Scientific Fund (No. 14-33-00009) and the Government of Russian Federation (Federal Agency of Scientific Organizations).

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