High-strength V95 aluminum alloy (Russian analogue of A7075 alloy) belongs to Al-Mg-Cu-Zn system. These alloys possess low corrosion resistance in atmospheric and water environments. The application of molybdate solutions for chemical oxidizing of aluminum alloys is one of perspective trends of chromateless converting formulations development. It has been shown earlier, that it is possible to obtain the chromateless conversion coatings on aluminum-magnesium alloys and aluminum-copper alloys of Al-Mg-Cu system in alkaline molybdate formulations modified by various oxidizers and corrosion inhibitors. The coatings with high protective properties were formed in the investigated converting formulations. In this connection, a study of chemical oxidizing in such converting formulations of V95 aluminum alloy with various heat treatments seemed interesting. The kinetics of conversion coatings formation on V95 alloys with various heat pretreatments in alkaline molybdate-borate converting formulations and their protective properties in chloride solutions were investigated by corrosion and electrochemical methods. The regularities of influence of the developed chromateless converting formulation IFHANAL-3 components on the protective properties and structure of conversion coatings on V95 alloy are revealed with the use of x-ray spectral microanalysis methods. It is shown, that low corrosion resistance to local anode activation in chloride solutions of coatings on alloy V95 is connected with their enrichment with zinc and copper oxides. The filling of the obtained conversion coatings in a solution of IFHAN-25 inhibitor increases their protective properties to chromate coatings level due to the adsorption inhibitor film formation on a coating surface. The tests of such coatings in the salt fog chamber have shown that their corrosion resistance exceeds 168 hours.
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