Corrosion Behavior of Steel Pre-treated with Silanes Available to Purchase

Steel panels were coated with ten different silanes by brushing the silane or a diluted silane on the surface, and the coated panels were evaluated for corrosion protection by measuring polarization resistance, anodic and cathodic polarization curves, electrochemical impedance, and accelerated rusting. Cathodic delamination tests were also performed on panels treated with three different silanes. The best overall corrosion protection was afforded by a coating formed from methyl triacetoxy silane. X-ray photoelectric spectroscopy (XPS), Auger electron spectroscopy (AES), and Fourier transformation infrared (FTIR) studies suggest that the active silanes provide a continuous coating that is not removed from the surface when exposed to aqueous solution. The more protective silanes show Si-O-Si bonds indicative of polymerization.