Print Email Facebook Twitter Interpreting electrochemical noise and monitoring local corrosion by means of highly resolved spatiotemporal real-time optics Title Interpreting electrochemical noise and monitoring local corrosion by means of highly resolved spatiotemporal real-time optics Author Denissen, P.J. (TU Delft Novel Aerospace Materials) Homborg, A.M. (Netherlands Defence Academy) Garcia, Santiago J. (TU Delft Novel Aerospace Materials) Date 2019 Abstract Real-time optical analysis is used to improve the interpretation of electrochemical noise signals (EN). The concept is presented for the case of AA2024-T3 under immersion in various NaCl concentrations. An in-house developed optical-electrochemical technique allowed for high spatiotemporal resolution and was used to visualize and quantify surface changes in parallel with monitoring EN signals. EN analysis was performed in the time-frequency domain using continuous wavelet transform (CWT). Correlations between the two procedures enabled the identification of corrosion processes in time, such as de-alloying, etching, pitting and subsurface corrosion. Besides this, optical measurements at higher magnification were used to analyse a smaller section of the exposed metal with a spatial resolution below 1 μm. This enabled the quantification on the size, number and nearest neighbor distance of local corrosion events, such as pits and corrosion rings. The set-up and optical protocol allowed for the first time (i) to establish a direct relationship between EN signals and the occurrence of specific localized corrosion phenomena and (ii) an in-situ highly-resolved monitoring of local corrosion processes. As a final result of the optical analysis we introduce a straightforward illustration that allows the direct identification of EN features to macroscopic local corrosion phenomena. To reference this document use: http://resolver.tudelft.nl/uuid:fd7542d4-3927-4490-bbf8-27901a6bd500 DOI https://doi.org/10.1149/2.0341911jes ISSN 0013-4651 Source Electrochemical Society. Journal, 166 (11), C3275-C3283 Part of collection Institutional Repository Document type journal article Rights © 2019 P.J. Denissen, A.M. Homborg, Santiago J. Garcia Files PDF J._Electrochem._Soc._2019 ... 275_83.pdf 1.99 MB Close viewer /islandora/object/uuid:fd7542d4-3927-4490-bbf8-27901a6bd500/datastream/OBJ/view