Effects of electrodeposition potential on the corrosion properties of bis-1,2-[triethoxysilyl] ethane films on aluminum alloy

Bis-1,2-[triethoxysilyl] ethane (BTSE) films were prepared on 2024-T3 alloys by using potentiostatic method for corrosion protection. This work mainly investigated the effects of electrodeposition potential on the corrosion properties of silane films. Films prepared at cathodic potentials display an improvement in corrosion inhibition properties, while those prepared at anodic potentials present the deterioration of protectiveness. In the case of cathodic deposition, when the potential shifts negatively from the open-circuit potential (OCP), corrosion protection of the obtained films initially increases and then decreases, with the optimal deposition potential at −0.8 V/SCE. As indicated in scanning electron microscopy (SEM) images, films deposited at the optimum potential present the most uniform and compact morphologies. In addition, steady-state polarization and current–time curves have been also recorded on Al alloys in BTSE solutions during the deposition, respectively.