Institute of Chemistry (Far Eastern Branch of Russian Academy of Sciences), Vladivostok, Russia:
V. S. Rudnev, Head of Laboratory of Plasma-Electrolytic Processes, e-mail: rudnevvs@ich.dvo.ru
P. M. Nedozorov, Researcher of Laboratory of Plasma-Electrolytic Processes
T. P. Yarovaya, Researcher of Laboratory of Plasma- Electrolytic Processes

Far Eastern Federal University, Vladivostok, Russia:

Yu. N. Mansurov, Head of a Chair “Materials Science and Material Technologies”

In certain cases there is a need in local application of oxide coatings by plasmaelectrolytic oxidation (PEO) on separate sites of surface without immersion of all product in bathtub with electrolyte. However regularities of such processes are not comprehensively studied. This paper shows the information on local application of coatings in the system “flat aluminum anode — sleeve cathode” from stainless steel. The data are obtained showing the influence of electrolyte consumption velocity via hollow cathode, interelectrode distance and time of processing for local coating spot diameter and thickness. Effect of local processing may be reached at certain velocities of electrolyte pumping and distance between electrodes. PEO-coating in the conditions of the electrolyte (freely falling via the cylindrical cathode nozzle) can be applied on a local site of a flat surface when the distance between electrodes is more than 1 mm, and electrolyte consumption velocity not less than 6 l/(min.cm2). These and other data may be taken as a basis when developing ways of drawing PEO-coatings on the necessary local sites of a surface of metal products. The laboratory installation was manteled allowing to investigate the experimentally processes of local drawing coatings on a surface of samples from aluminum-magnesium alloys by PEO.

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