The Deposition Mechanism and Protective Properties of Manganese-Based Conversion Coatings on the Surface of AD31 Aluminum Alloy

The stage mechanism of manganese-containing conversion coatings (MCCs) formation on the surface of AD31 alloy (AA6063) in acidic (pH 3) KMnO4 solutions, as well as their structure, composition, and anticorrosion properties have been examined using scanning electron microscopy, energy dispersive X-ray microanalysis, Raman spectroscopy, UV-Vis spectroscopy, electrochemical impedance spectroscopy, potentiodynamic polarization, and salt spray chamber tests. The conditions for obtaining MCCs have been optimized, and the feasibility of their use in multicomponent corrosion protection systems for the AD31 aluminum alloy has been shown.