The role of yttrium oxide on the corrosion resistance of BTSE silane films on AA6061

The results of potentiodynamic polarization curves, impedance spectroscopy (EIS) reveal that the presence of small amounts of Y2O3 in BTSE solutions can increase the corrosion resistance of the silane films in 3.5% NaCl solution. The formed film does not change the dynamic behaviors of the electrode reaction; it mainly inhibits the cathodic reduction reaction of electrochemical corrosion and acts as a physical barrier for the protection of aluminum alloy. The scanning electron microscopy (SEM) images indicated that the surface morphologies of silane films formed were flat and compact, with high cross-link density, when the contents of Y2O3 in BTSE solutions were 10mg/L and 20mg/L.