Corrosion properties of composite coatings on AMg3 alloy surface

Abstract

Method of the composite polymer-containing coatings formation on the AMg3 aluminum alloy by plasma electrolytic oxidation (PEO) with the subsequent application of a polymer from the suspension of superdispersed polytetrafluoroethylene is presented. The optimal parameters such as a multiplicity of the application, the temperature and the time of heat treatment were determinate in order to obtain coatings with the highest protective properties. Composite layers significantly improve the anticorrosion properties of aluminum alloy, reducing corrosion current density by 2 orders of magnitude in comparison with the base PEO-coating. This makes it possible to significantly reduce the possibility of corrosion damage of the protective coating during operation, and, consequently, improve its reliability.