Comparing Electrochemical Impedance Spectroscopy Methods for Estimating the Degree of Delamination of Organic Coatings on Steel

Author(s)

S. A. McCluney, Texas A & M University - College Station
S. N. Popova, Texas A & M University - College StationFollow
Branko N. Popov, University of South Carolina - ColumbiaFollow
Ralph E. White, University of South Carolina - ColumbiaFollow
R. B. Griffin, Texas A & M University - College Station

Document Type

Article

Subject Area(s)

Chemical Engineering

Abstract

Electrochemical impedance spectroscopy (EIS) was used to evaluate the degree of delamination of the epoxy primer Uniprime ED-4¹ electrocoated on phosphate-treated cold-rolled steel in 3.5% NaCl exposed to air. Specimens with coating thicknesses of 20.3 and 20.8 µm and surface areas of 78.5 cm² were used. Coating parameters were obtained using a circuit-analog model. The area of delamination was estimated using several EIS parameters, including the pore resistance and the break point frequency. These values were compared to the corroded area determined visually. All methods considered exhibited a strong correlation over some or all of the range of exposure times.

Publication Info

Journal of the Electrochemical Society, 1992, pages 1556-1560.

Rights

© The Electrochemical Society, Inc. 1992. All rights reserved. Except as provided under U.S. copyright law, this work may not be reproduced, resold, distributed, or modified without the express permission of The Electrochemical Society (ECS). The archival version of this work was published in the Journal of the Electrochemical Society.

http://www.electrochem.org/

DOI: 10.1149/1.2069454

http://dx.doi.org/10.1149/1.2069454