Corrosion behaviour of the yttria stabilized sol-gel ZrO_2 thin film on 316L stainless steel

摘要

In this paper, one layer and three layers of yttria stabilized sol-gel ZrO_2 thin filmswere deposited on the X2CrNiMo17-12-2 (AISI 316L) austenitic stainless steel by dipcoating method. For the preparation of sol zirconium(IV) butoxide was used as precursor,i-propanol as a solvent with addition of nitric acid as a catalyst, acetylacetoneas chelating agent and water for hydrolysis. Deposited films were calcined at thetemperature of 400 ℃.Thickness of sol-gel ZrO_2 films deposited on stainless steel was determined by glowdischargeoptical emission spectrometry (GD-OES). It was found that thickness ofdeposited films increases by increasing the number of layers.Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization insimulated marine environment (3.5 wt. % NaCl aqueous solution) were used to determinethe corrosion behaviour of ZrO_2 coated stainless steel. The influence of ZrO_2layers number on the degree of the protection was examined as well. It was foundthat the sol-gel ZrO_2 films are able to make an appreciable improvement in the corrosionresistance of stainless steel in the investigated corrosive medium.