Improving corrosion protection of Al97Mg3 alloy in neutral sodium chloride solution by 1,2-bis(triethoxysilyl)ethane coating

We studied the protection of Al97Mg3 (Aluminium alloy 5754) against corrosion in neutral 3.5% NaCl solution by applying films of 1,2-bis(triethoxysilyl)ethane. The electrochemical characteristics of bare and coated alloy were evaluated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS). The surface morphologies and structures were assessed from field-emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray spectroscopy techniques (EDX) measurements. We used a simple immersion technique to achieve silane films formation over the alloy surface. The protection of the surface is due to the formation of a highly cross-linked and dense layer that developed at the interface between the silane film and the aluminum oxide.