Corrosion study of SiO₂–CaO–Al₂O₃–Na₂O–TiO₂ glass coating on steel

A protective coating of 60SiO₂–15CaO–10Al₂O₃–10Na₂O–5TiO₂ glass ceramic was performed on the ferritic stainless steel substrate by slurry technique. X-ray diffraction and scanning electron microscopy were used for detailed analyses of the coating. Open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarisation studies were carried out in artificial seawater to monitor the corrosion resistance behaviour of the coating at room temperature. The presence of coating reduced the corrosion current density I_corr and shifted corrosion potential E_corr towards more noble values. It has been established through this study that glass ceramic coating on the steel substrate essentially improves the corrosion resistance property of the alloy and can be used for marine applications.