Effect of Different Zirconium Contents on the Corrosion Resistance of ZrO2-TiO2 Film-Coated Stainless Steel

This work discusses the corrosion resistance of x%zirconia (ZrO2)-x%titania (TiO2) nanocomposite films with different percentages of ZrO2 prepared on stainless steel by dipping the substrates in sol-gel solutions. The phase compositions and microstructures of the films were investigated by x-ray diffraction (XRD) and scanning electron microscopy (SEM). Tafel polarization curves and electrochemical impedance spectroscopy (EIS) were employed to investigate the corrosion resistance of the coated steel substrates during immersion in a 5% NaCl solution at room temperature. The results showed that when the percentage of ZrO2 in the sol-gel was relatively low, the film contained cracks, leading to a poor corrosion resistance. When the percentage of ZrO2 was higher, the corrosion resistance of the film was also affected by the sintering temperature; a sintering temperature of 650 degrees C gave the best protection of the metal surface, and the protection efficiency was 95%.