Etude electrochimique, et par microscopie electronique a balayage, du fer recouvert de peinture

Constant-phase-element behavior caused by inhomogeneous water uptake in anti-corrosion coatings

“…In Fig. 9, the low-frequency limit of the coating impedance is close to R pore , i.e., the pseudo-diameter of the highfrequency loop may be identified with the pore resistance as for the classical Beaunier's circuit [2], and, therefore, the high-frequency loop is almost symmetrical with respect to the Z" maximum (compare with Fig. 6c).…”

“…Electrochemical impedance spectroscopy is a popular technique for the assessment of the corrosion protection performance of organic coatings, which has been used for some decades [1][2][3][4][5]. By following the evolution of the impedance response of a substrate/coating/electrolyte system over an extended period of time, many research groups have been able to monitor the degradation of the coating material and the onset of corrosion processes.…”

A study of performance of corrosion prevention compounds on AA2024-T3 with electrochemical impedance spectroscopy

“…Polarization resistance (R p ) and double layer capacitance (C dl ) values were obtained by fitting the impedance spectra to equivalent circuit models with ZView ® (Scribner Associates, Southern Pines, NC). The equivalent circuit models used were generally of the form shown by Beaunier et al [16] and Mansfeld et al [17], although in some cases, a Warburg element was added to improve the fit. The electrochemical parameters, such as polarization resistance and double layer capacitance, were extracted from the fitted data.…”

Identification of Resistivity Distributions in Dielectric Layers by Measurement Model Analysis of Impedance Spectroscopy

“…Beaunier et al [8] proposed a general model in which the ohmic resistance is in series with the parallel combination of the capacitance of the polymer coating and the electrolyte resistance in the pores; the latter is in series with the parallel combination of double layer capacity and faradaic impedance of the wet area at the metal/coating interface. This model was modified by Mansfeld [9], who replaced the faradaic impedance of the corrosion process with a polarization resistance.…”

“…This model was modified by Mansfeld [9], who replaced the faradaic impedance of the corrosion process with a polarization resistance. The faradaic impedance of Beaunier et al [8] was treated by Hirayama and Haruyama [10] in terms of quantities that accounted for the parallel contributions of reactions at the metal/coating interface and at exposed metal surface by pores or coating defects. Upadhyay et al [11] found that impedance responses of glycidyl carbamate functional coatings were closely related to structural and compositional variations.…”