Royal Military College of Canada, Kingston, Ontario
Pages: 15 Published: Jan 1992
The statistical validation of a resistance-capacitance (RC) model from a limited number of data points can be achieved by systematically permuting the three data points that are chosen to extrapolate the centers of semicircular impedance diagrams. An earlier version of the geometric analysis technique, which consisted of finding geometrically the center of an arc formed by the successive data points on a complex impedance diagram, had been successfully applied to the study of erosion corrosion mechanisms of some copper nickel alloys submitted to highly turbulent conditions.
A series of results obtained with a combination of alloy composition, exposure conditions, and environments seems to indicate that the nonadherence to a perfect RC model by electrochemical impedance data provides information concerning the types of corrosion processes occurring on a metallic surface. The analytical method developed to reveal these fundamental characteristics of impedance patterns will be critically detailed with particular emphasis on the parameters controlling its resolution and on its ease of implementation.
electrochemical impedance spectroscopy, localized corrosion, corrosion monitoring, carbon steel, copper-nickel, erosion corrosion
Paper ID: STP24697S