Electrochemical Impedance Spectroscopy on 3-D Inhomogeneous Surfaces Corrosion Inhibition of Carbon Steel in Weakly Acidic NaCl Solutions

1988 ◽  
Vol 92 (11) ◽  
pp. 1234-1244 ◽  
Author(s):  
M. Mitzlaff ◽  
H. N. Hoffmann ◽  
K. Jüttner ◽  
W. J. Lorenz
2021 ◽  
pp. 33-53
Author(s):  
A.N. El-hoshoudy ◽  
M. Abd El-Raouf ◽  
M. M. Attya ◽  
Ahmed A. Fadda ◽  
M. Waly

Corrosion behavior of X65-type carbon steel exposed to 1M HCl aqueous solution was studied in the absence and presence of various concentrations of new synthesized 3-(4-chlorophenyl)-2-cyano-N-(4-hydroxyphenyl) acrylamide, abbreviated as (P2), and 6-amino-4-(4-chlorophenyl)-1-(4-hydroxyphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile, abbreviated as (P3), at 25oC. Potentiodynamic polarization data indicated that the synthesized Cyanoacetamide derivatives suppress both anodic and cathodic reactions via adsorption on the carbon steel surface and blocking the active sites. The adsorption of the inhibitor molecules forms a protective film which decreases the surface heterogeneity. Electrochemical impedance spectroscopy (EIS) measurements reveal that as the inhibitor concentration is increased, both the inhibition efficiency (η%) and the charge transfer resistance (Rt) are increased while the electrochemical double layer capacity (Cdl) is decreased. The experimental impedance data were analyzed according to a proposed equivalent circuit model for the electrode/electrolyte interface. Chemical descriptors are calculated through the density functional theory (DFT), also adsorption of inhibitors on the metal surface investigated through Monte Carlo simulation. The mechanism of corrosion inhibition was discussed given the obtained results of surface analysis and the molecular structure of the additive obtained from quantum chemical calculations. Keywords: Corrosion inhibition; Polarization; Electrochemical impedance spectroscopy (EIS); Surface analysis; Quantum chemical calculations


2013 ◽  
Vol 781-784 ◽  
pp. 299-303
Author(s):  
Shu Lan Cai ◽  
Kang Quan Qiao ◽  
Fa Mei Feng

A new corrosion inhibior N,N-diethylammonium O,O-di (p-chlorophenyl) dithiophosphate (EDPDP) has been synthesized and its inhibition effect towards the corrosion of carbon steel in 1.0 molL-1 HCl solution at 25 °C has been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. The obtained results show that EDPDP is a excellent inhibitor and the inhibition efficiencies exceed 90 %. The polarization measurements reveal that EDPDP is a mixed type inhibitor and the equivalent circuit model of the corrosion inhibition process is obtained by the analysis of EIS data.


2019 ◽  
Vol 43 (16) ◽  
pp. 6303-6313 ◽  
Author(s):  
Ambrish Singh ◽  
K. R. Ansari ◽  
M. A. Quraishi ◽  
Savas Kaya ◽  
Priyabrata Banerjee

The corrosion inhibition behavior of a naphthoxazinone derivative 1-phenyl-1,2-dihydronaphtho[1,2-e][1,3]oxazin-3-one (PNO) on J55 steel in 3.5 wt% NaCl solution saturated with carbon dioxide was evaluated using weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2611
Author(s):  
Esther Udabe ◽  
Anthony Sommers ◽  
Maria Forsyth ◽  
David Mecerreyes

Chromate free corrosion inhibitors are searched for to mitigate the economic loss caused by mid-steel corrosion. Here, we show metal-free organic inhibitors having free coumarate anions that can be used either as direct corrosion inhibitors or incorporated into a polymer coating obtained by UV-curing. Four different ionic liquid monomers and polymer coatings with hexoxycoumarate anion and different polymerizable counter cations were investigated. Potentiodynamic polarization, electrochemical impedance spectroscopy, and surface analyses have verified their corrosion inhibition performance on a mild steel AS1020 surface. In the case of the coumarate ionic liquid monomers, the most promising inhibitor is the one coupled with the ammonium cation, showing an inhibition efficiency of 99.1% in solution followed by the imidazolium, pyridinium, and anilinium. Next, the ionic liquid monomers were covalently integrated into an acrylic polymer coating by UV-photopolymerization. In this case, the barrier effect of the polymer coating is combined with the corrosion inhibitor effect of the pendant coumarate anion. Here, the best polymer coatings are those containing 20% imidazolium and pyridinium cations, presenting a greater impedance in the EIS (Electrochemical Impedance Spectroscopy) measurements and less evidence of corrosion in the scribe tests. This article shows that the cationic moiety of coumarate based ionic liquids and poly(ionic liquid)s has a significant effect on their excellent corrosion inhibition properties for a mild steel surface exposed to aqueous chloride solutions.


2013 ◽  
Vol 652-654 ◽  
pp. 1432-1435
Author(s):  
Qian Hu ◽  
Jing Liu ◽  
Jie Zhang ◽  
Feng Huang ◽  
Xing Peng Guo

The crevice corrosion behaviors of X52 carbon steel in two typical Cl--containing solutions were investigated by electrochemical noise and electrochemical impedance spectroscopy. Results show that oxygen concentration difference leads to the coupled current in NaCl + NaHCO3 solution while HAc concentration difference causes the coupled current in NaCl solution saturated with CO2 in the presence of HAc. There exists an apparent incubation stage during the crevice corrosion process of X52 carbon steel in the former. However, no obvious incubation period of crevice corrosion can be observed in the latter. Micrography shows that the crevice corrosion occurs indeed and the corrosion inside the crevice is not uniform.


2018 ◽  
Vol 4 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Nilesh S. Bagal ◽  
Vaibhav S. Kathavate ◽  
Pravin P. Deshpande

AbstractThe present study aims at deposition of zinc phosphate coatings on low carbon steel with incorporated nano- TiO2 particles by chemical phosphating method. The coated low carbon steel samples were assessed in corrosion studies using electrochemical impedance spectroscopy and potentiodynamic polarization techniques (Tafel) in 3.5% NaCl solution. Morphology and chemical composition of the coatings were analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy in order to observe growth of coating. Significant variations in the coating weight, porosity and corrosion resistance were observed with the addition of nano- TiO2 in the phosphating bath. Corrosion rate of nano-TiO2 chemical phosphate coated samples was found to be 3.5 milli inches per year which was 3 times less than the normal phosphate-coated sample (8 mpy). Electrochemical impedance spectroscopy studies reveal reduction of porosity of nano-TiO2 phosphate coated samples. It was found that nano-TiO2 particles in the phosphating solution yielded uniform phosphate coatings of higher coating weight, fewer defects and enhanced corrosion resistance than the normal zinc phosphate coatings (developed using normal phosphating bath).


2019 ◽  
Vol 43 (1) ◽  
pp. 71-77 ◽  
Author(s):  
Adriano H. Akita ◽  
Cecílio S. Fugivara ◽  
Idalina V. Aoki ◽  
Assis V. Benedetti

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