Evaluation of Passivation and Corrosion Behavior of AISI 316L SS with Low Ferrite Content Using EIS Test in Artificial Seawater Solution

In this study, the electrochemical behavior of AISI 316L Austenitic Stainless Steel with low ferrite content, aged at temperatures ranging from 550 to 700 °C for ranging times of 50 to 80.000 h, was followed by Electrochemical Impedance Spectroscopy (EIS). This technique is becoming increasingly tool used to characterize and determine the properties of the passive film formed on the surface of stainless steels. The obtained results were comprehensively discussed and then used to develop a specific models based on Equivalent Electrical Circuits (EEC). These models were exploited to predict the formation of the passivity film during the aging of AISI 316L austenitic steels. A good agreement between the experimental results and those obtained by the models was observed.