Anti-corrosive characterization of silicon, titanium, and zirconium oxide coatings deposited on aeronautical aluminum substrates via sol-gel

Abstract

Currently, aircraft wings made of AA2024 T3 aluminum are primed between the aluminum substrate and the outer layer of paint to improve the material's adhesion and corrosion resistance. This type of primer contains chromates whose treatment generates highly toxic hexavalent chromium. This work studied the effect of applying dip-coating coatings of combined silicon, titanium, and zirconium oxides on AA2024 T3 aluminum substrates synthesized via sol-gel. The influence of the number of layers on the substrates anti-corrosive behavior in a 3% NaCl solution was studied using electrochemical impedance spectroscopy techniques and potentiodynamic polarization curves. The substrates corrosion resistance was found to improve substantially concerning the number of layers deposited.