Corrosion Behavior of Amorphous Sol-Gel TiO2-ZrO2 Nano Thickness Film on Stainless Steel

In this work, a single-layer TiO2-ZrO2 thin film is deposited on the AISI 316L austenitic stainless steel by the sol-gel process and the dip coating method to improve its corrosion resistance properties. For the sol preparation, titanium isopropoxide and zirconium butoxide are used as the precursors, yttrium acetate hydrate is used for the ZrO2 stabilization, i-propanol as the solvent, nitric acid as the catalyst, acetylacetone as the chelating agent, and the distilled water for the hydrolysis. The deposited films are annealed at 400 degrees C or 600 degrees C. Morphology and phase composition of the sol-gel TiO2-ZrO2 films and powders are analyzed by scanning electron microscopy (SEM) equipped with EDX detector and X-ray diffraction (XRD), respectively. The thickness of the sol-gel TiO2-ZrO2 films deposited on the stainless steel is determined by glow discharge optical emission spectrometry (GD-OES). The corrosion behavior of the stainless steel, coated by amorphous films, is evaluated in 3 wt% NaCl and 0.5 mol dm(-3) HCl by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. It is found that the sol-gel TiO2-ZrO2 films with the amorphous structure, deposited by the sol-gel process, and calcined at 400 degrees C significantly enhance the corrosion properties of AISI 316L in both chloride media.

Automated summary

In this study, a single-layer TiO2-ZrO2 thin film was deposited on stainless steel using the sol-gel process to enhance corrosion resistance. The film was analyzed for morphology and phase composition using SEM and XRD, and its thickness was determined by GD-OES. The corrosion behavior of the coated stainless steel was evaluated in different chloride media, showing significant improvement in corrosion properties with the sol-gel process and calcination at 400 degrees C.