Electrochemical Impedance Spectroscopy for Coating Evaluation using a Micro Sensor

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Published Sep 29, 2014
Nicholas Waters Richard Connolly Douglas Brown Bernard Laskowski

Abstract

This paper discusses a micro-linear polarization resistance (μLPR) sensor modified to perform coating evaluation by means of electrochemical impedance spectroscopy (EIS). A circuit model is used with the EIS data to measure solution resistance, pore resistance, charge transfer resistance, intact coating capacitance, and double layer capacitance. These measurements allow the end user to monitor degradation of protective coatings in real-time, through non-destructive means. This is demonstrated through an accelerated aging test using a coated metal plate with a modified μLPR sensor. A metal panel made from aluminum alloy 7075-T6 was coated with 2 mils of an epoxy-based polymer coating and 2 mils of high solids polyurethane. The sensor was adhered to the face of the coated panel in a manner that allowed the electrolyte solution consisting of 3.5% NaCl to flow between the sensor and the coated surface of the panel. EIS measurements were acquired every hour for a total of 35 hours and at the conclusion of the test, changes in key parameters within the circuit model identified the initial time and mechanism of coating degradation, in this case, delamination

How to Cite

Waters, N. ., Connolly, R. ., Brown, D. ., & Laskowski, B. . (2014). Electrochemical Impedance Spectroscopy for Coating Evaluation using a Micro Sensor. Annual Conference of the PHM Society, 6(1). https://doi.org/10.36001/phmconf.2014.v6i1.2340
Abstract 487 | PDF Downloads 634

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Keywords

corrosion, structural health monitoring, Electrochemical Impedance Spectroscopy, EIS, Coating Evaluation, Paint

References
Engineering Asset Management: Issues and Challenges. University of Cambridge, Cambridge, UK, Executive Briefing, 2012 Service Week Workshop on the Future of Asset Management, 2012.

Brown, D. W., Connolly, R. J., Darr, D. R., & Laskwoski, B. C. (2014). Linear Polarization Resistance Sensor Using the Structure as a Working Electrode (pp. 1-7), July 8-10, Nantes, France.

Loveday, D., Peterson, P., and Rodgers, B. 2004. Evaluation of Organic Coatings with Electrochemical Impedance Spectroscopy. JCT coatingstech, 2(13), pp.22-27.

Cano, E., Lafuente D., and Bastidas, D. M. , 2010. Use of EIS for the Evaluation of the Protective Properties of Coatings for Metallic Cultural Heritage: a Review. J. Solid State Electrochem, 14(3), pp.381-91.

Hyndman, R. J., & Koehler, A. B. (2006). Another look at measures of forecast accuracy. International Journal of Forecasting, vol. 22, pp. 679-688. doi:10.1016/j.ijforecast.2006.03.001.
Gamry Instruments, 2011. Rapid Electrochemical Assessment of Paint. Application Note. Warminster, PA: Gamry Instruments.

Deen, K. M. and Khan, I. H. 2009. Corrosion Protection Evaluation of Mild Steel Painted Surface by Electrochemical Impedance Spectroscopy. Journal of Quality and Technology Management, V1, paper 6.

Popoola, A., Olorunniwo, O. E., and Ige, O.O., 2014. Corrosion Resistance Through the Application of Anti- Corrosion Coatings.

Butt, M. T. Z., Deen, K.M., and Majeed, U. n.d. Evaluation of the Protective Performance of Epoxy Coated Mild Steel by Electrochemical Impedance Spectroscopy. Online. University
of the Punjab.

O’Donoghue, M., Garrett, R., Datta, V., and Roberts, P., 2003. Electrochemical Impedance Spectroscopy: Testing Coatings for Rapid Immersion Service. Materials Performace, pp.36-41.
Section
Poster Presentations