A Comparison Study on Corrosion Resistance of 430 Stainless Steel Surfaces Modified by Alkylsilane and Fluoroalkylsilane SAMs

The self-assembly monolayers (SAMs) of n-dodecyltriethoxysilane (DTES) and 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (PFDS) on the surface of the 430 stainless steel (430SS) were prepared and their corrosion protection performance was investigated by potentiodynamic polarization, Fourier transform infrared spectroscopy (FTIR) -attenuated total reflection (ATR), static contact angle and atomic force microscopy (AFM). The results showed that the alkali pretreatment and the water added into the self-assembly solution could generate more hydroxyls on the 430SS surface, and then enhanced the adsorption of the SAMs. A suitable temperature of the self-assembly solution is important for the formation of the SAMs. The silane SAMs were chemically adsorbed on the 430SS substrates by Fe-O-Si bonds. In all cases tested, PFDS has a better inhibition effect compared with DTES, and the difference in inhibition effect is most marked at the lowest concentration of 1 mmol/L.