Polymeric epoxy-based composites are modified with nanopowders of silicon oxide (similar to 100 nm). By the method of spraying, these composites are applied to specimens of 2024-T3 aluminum alloy preliminary treated with molybdate solutions to get conversion layers. Three types of polymeric coatings are considered: reference, treated by silica, and with additional polyurethane coatings. The aim of modification of polymeric coatings is to absorb and/or block unwanted ions/molecules (Cl-, O-2, OH-, H2O, etc.) and improve the protective properties of the films. The tests carried out by the method of electrochemical impedance spectroscopy, in a salt-fog chamber, and by immersion in a 0.5 M NaCl solution reveal high anticorrosion characteristics of the coating. New coatings are promising for the corrosion protection in the aircraft industry.
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