Corrosion inhibition properties of SiO2-ZrO2 nanocomposite coating on carbon steel 178

Abstract

Purpose SiO2 and SiO2-ZrO2 nanocomposites were coated by sol–gel dipping method on carbon steel 178 (178 CS). Nanostructure and phase properties of nanocomposite coating were characterized using X-ray diffraction, scanning electron microscopy and Fourier transform infrared studies. Electrochemical polarization and electrochemical impedance spectroscopy (EIS) tests were used to study the corrosion behavior of 178 CS that was coated with SiO2-ZrO2 nanocomposite and SiO2 coating in 3.5 per cent NaCl solution. The results indicated that SiO2-ZrO2 nanocomposite coating performed better in terms of corrosion resistance compared with SiO2 coating. The corrosion resistance of SiO2-ZrO2 nanocomposite coating could be increased significantly in by approximately three and seven times of that of SiO2 coating and bare 178 CS, respectively. Design/methodology/approach SiO2 and SiO2-ZrO2 nanocomposites were coated using sol–gel dipping method on carbon steel 178. Electrochemical polarization and EIS tests have been used to study the corrosion behavior of 178 CS that was coated with SiO2-ZrO2 nanocomposite and SiO2 coating in 3.5 per cent NaCl solution. Findings Results indicated that SiO2-ZrO2 nanocomposite coating performed better in terms of corrosion resistance compared with SiO2 coating. The corrosion resistance of SiO2-ZrO2 nanocomposite coating could be increased significantly in by approximately three and seven times of that of SiO2 coating and bare 178 CS, respectively. Originality/value The SiO2-ZrO2 nanocomposite coating film showed significant improvement in corrosion resistance of 178 CS. The highest polarization resistance of the nanocomposite coating film was 10,600 Ω/cm2 from SiO2-0.2 ZrO2.