On-line corrosion and corrosion-wear monitoring using a modified electrochemical noise technique

In this study, a modified electrochemical noise (EN) technique was used to monitor uniform corrosion and pitting corrosion. In the EN technique, one working electrode is coupled to a microelectrode (e.g. Pt) through a zero resistance ammeter to sense current noise. Results show that the EN technique with a properly selected microelectrode appears to be able to distinguish different corrosion processes like uniform corrosion on mild carbon steel and pitting corrosion on stainless steel. Furthermore, this EN technique was successfully implemented in on-line corrosion-wear monitoring of stainless steel. In addition, the modified EN technique can sensitively detect the interface of nitrogen ion implanted layer and the stainless steel substrate, thus determining the thickness of the implanted layer.