Application of EIS Technique to Evaluation for Protective Properties of Rust on Weathering Steel

Abstract

In order to establish a diagnostic technique to check the status of rust formed on weathering steel, the corrosion protection mechanism by rust was studied using EIS technique. The impedance appeared in intermediate frequency range was attributed to ion transfer through the rust, which was concluded as a quantitative measure for its protective properties. Based on these findings, a compact instrument was developed to facilitate in-situ monitoring the surface condition of existing weathering steel structures.