Influence of potassium and sodium metasilicate in electrolyte hydrocsida on micro-hardness of MDO coating

The results of studies of the effect of the content of potassium hydroxide and sodium metasilicate in the electrolyte on the microhardness of coatings formed by microarc oxidation (MAO) on plastically deformed aluminum alloys AO3-7 and AK-7ch, from which the sleeves and casings of gear pumps of the NSh type are made. -We. The results of experimental studies have shown that by changing the content of components in the electrolyte and MAO modes, the microhardness of coatings formed by the MAO method on plastically deformed alloys can be varied within wide limits. That makes it possible to apply these coatings to harden the working surfaces of parts made of aluminum alloys, which function in different conditions. In the work, the optimal content of electrolyte components and MAO modes was selected, at which the maximum microhardness of the resulting coatings is achieved.