A Novel Sensing T echnique for Monitoring Pitting Corrosion of Stainless Steel T ype 316L
Naing Naing Aung* and Y ong- Jun T an* Author for corresponding; e-mail address: p115573@ntu.edu.sg
Volume: Vol.32 No.3 (SEPTEMBER 2005)
Research Article
DOI:
Received: -, Revised: -, Accepted: -, Published: -
Citation: Aung N.N. and An Y.O.J.T., A Novel Sensing T echnique for Monitoring Pitting Corrosion of Stainless Steel T ype 316L, Chiang Mai Journal of Science, 2005; 32(3): 521-527.
Abstract
A novel electrochemically integrated multi-electrode array namely the wire beam electrode (WBE) in combination with noise signatures analysis has been designed to monitor pitting corrosion of one of the best corrosion resistance ferrous alloys, stainless steel type 316L. From the direct correlation of electrochemical potential noise signatures and galvanic current distribution maps during pitting corrosion processes, two characteristic noise patterns were observed prior to stable pit formation: (i) the characteristic peak of rapid potential transient, towards less negative direction, followed by recovery (termed noise signature I) was found to correlate with the disappearance of unstable anode; (ii) the characteristic noise pattern of quick potential changes towards less negative direction followed by no recovery (termed noise signature II) was found to correspond with the massive disappearance of minor anodes leading to formation of highly localized major anodes in the galvanic current distribution maps.