Corrosion Protection of Steel by Volatile Corrosion Inhibitors: Vapor Analysis by Gas-Diffusion Microextraction and Mass Loss and Electrochemical Impedance in NaCl Deliquescence Tests

The search for highly effective corrosion protection solutions to avoid degradation of the metallic parts is enabling the development of polymeric organic coatings. Of particular relevance, polymeric nanocomposite coatings, modified with corrosion inhibitors, have been developed to provide enhanced surface protection. In this work, yttrium oxide nanoparticles loaded with corrosion inhibitor (Imidazole), used as additives in the formulation of epoxy for coated on the steel substrate. The loading of Y2O3 with imidazole was confirmed by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller analysis. UV-Vis analysis demonstrated the pH-sensitive behavior of the imidazole that helps in self-release when necessary. Electrochemical impedance spectroscopy (EIS) of the coated samples revealed that the coating modified with Y2O3/IMD provides better corrosion protection compared to coatings containing only Y2O3. XPS analysis validated the presence of an imidazole protective film on the steel substrate that enhanced the corrosion resistance of the coated samples

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Protection of Aluminium Alloys via Hybrid Sol-Gel Coatings with Encapsulated Organic Corrosion Inhibitors

Materials Science Forum ◽

10.4028/www.scientific.net/msf.519-521.661 ◽

2006 ◽

Vol 519-521 ◽

pp. 661-666 ◽

Cited By ~ 1

Author(s):

A.N. Khramov ◽

V.N. Balbyshev ◽

R.A. Mantz

Keyword(s):

Corrosion Protection ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Substrate Surface ◽

Sol Gel ◽

Matrix Material ◽

The Matrix ◽

Aluminum Alloy 2024 ◽

Structural Hybrid ◽

Organic Corrosion Inhibitors

Several heterocyclic organic corrosion inhibitors that contain ionazible functional group were encapsulated into nano-structural hybrid organo-silicate coating to improve its corrosion protection performance on aluminum alloy 2024-T3 substrate. When the coating is formed on the substrate surface, it serves simultaneously as protective barrier and as a reservoir for leachable corrosion inhibitor that is stored and released through the mechanism of reversible ionic interaction with the matrix material. The efficiency of active corrosion protection for these coating systems was examined by electrochemical methods including potentiodynamic polarization (PDS) and electrochemical impedance spectroscopy (EIS). The effects of chemical structure and the loading concentration of the inhibitor within the coating were determined.

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Synthesis of Oxide Nanoparticles in Hybrid Nanocomposite Coatings as Nanoreservoirs of Corrosion Inhibitors

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512002073 ◽

2012 ◽

Vol 05 ◽

pp. 234-241 ◽

Cited By ~ 1

Author(s):

NAHID PIRHADY TAVANDASHTI ◽

SOHRAB SANJABI

Keyword(s):

Corrosion Protection ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Sol Gel ◽

Oxide Nanoparticles ◽

Prolonged Release ◽

Self Healing ◽

Boehmite Nanoparticles ◽

Healing Property ◽

Sol Gel Films

Nanostructured hybrid silica/epoxy films containing boehmite nanoparticles were investigated in the present work as pretreatments for AA2024 alloy. To produce the nanocomposite sol-gel films, boehmite nanoparticles prepared from hydrolysis/condensation of aluminum isopropoxide ( AlI ) were doped into another hybrid organosiloxane sol. The produced oxide nanoparticles have the capability to act as nanoreservoirs of corrosion inhibitors, releasing them controllably to protect the metallic substrate from corrosion. For this purpose the corrosion inhibitor, cerium nitrate, was introduced into the sol-gel system via loading the nanoparticles. The morphology and the structure of the hybrid sol-gel films were studied by Scanning Electron Microscopy (SEM). The corrosion protection properties of the films were investigated by Potentiodynamic Scanning (PDS) and Electrochemical Impedance Spectroscopy (EIS). The results show that the presence of boehmite nanoparticles highly improved the corrosion protection performance of the silica/epoxy coatings. Moreover, they can act as nanoreservoirs of corrosion inhibitors and provide prolonged release of cerium ions, offering a self-healing property to the film.

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Investigation of Using Sol-Gel Technology for Corrosion Protection Coating Systems Incorporating Colours and Inhibitors

Coatings ◽

10.3390/coatings9010052 ◽

2019 ◽

Vol 9 (1) ◽

pp. 52 ◽

Cited By ~ 1

Author(s):

Wenjin Yan ◽

Wee Kit Ong ◽

Linda Yongling Wu ◽

Sudesh L. Wijesinghe

Keyword(s):

Corrosion Protection ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Sol Gel ◽

System A ◽

Number Of Layers ◽

Mechanical And Physical Properties ◽

Corrosion Protection Coating ◽

Protection Coating ◽

Vital Factor

Corrosion protection coatings need frequent developments to cater to different challenges arising from users. In addition to a long lasting corrosion protection, aesthetic requirements and multi-functional properties by the same coating system are prominent demands to be considered. Productivity is another vital factor to be considered, as there is a thriving demand from users to have more productive coating systems, such as a smaller number of layers in a system. Thus, attention to using different coating technologies is an essential step to fulfil these demands. This work investigates the use of sol-gel technology as a topcoat on a zinc rich primer to form a two-coat system. A colored sol-gel topcoat on a zinc primer was developed as a two-coat system to replace the current three or multi-coat systems to improve productivity while maintaining the sacrificial protective capability. The overall corrosion protection performance together with the color retaining capability was evaluated in this development. As another step forward, the development of sol-gel technology as a topcoat with additional inhibitive corrosion protection was investigated. Two corrosion inhibitors, namely molybdate and cerium(III), were loaded onto suitable inorganic oxide carriers and then incorporated into sol-gel coatings to provide an inhibitive protection other than the barrier protection. The corrosion performance of the coatings was evaluated using electrochemical impedance spectroscopy (EIS). Sol-gel coating with a cerium(III) system attained the highest impedance and proved to be the best candidate. The mechanical and physical properties of the coating systems are tested using international standard methods.

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Effect of polyaniline/montmorillonite content on the corrosion protection of epoxy coating

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-03-2015-1511 ◽

2017 ◽

Vol 64 (1) ◽

pp. 75-82 ◽

Cited By ~ 3

Author(s):

Yingjun Zhang ◽

Yawei Shao ◽

Qiumei Shi ◽

Yanqiu Wang ◽

Guozhe Meng ◽

...

Keyword(s):

Corrosion Protection ◽

Design Methodology ◽

Composite Powder ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Barrier Properties ◽

Metal Substrate ◽

Scanning Calorimetry ◽

Content Type ◽

Powder Content

Purpose The purpose of this paper was to research the influence of polyaniline/montmorillonite (PANI/OMMT) composite powder content on the corrosion protection of epoxy (EP) coating. Design/methodology/approach The polyaniline/montmorillonite/epoxy (PANI/OMMT/EP) coatings containing different contents of PANI/OMMT composite powder were prepared on steel. The corrosion protection performances of PANI/OMMT/EP coatings in 3.5 per cent NaCl solutions were investigated by electrochemical impedance spectroscopy. The barrier property of coatings was examined using water absorption analysis. The structure and crosslink density of coatings were examined using scanning electron microscopy and differential scanning calorimetry, respectively. Findings The PANI/OMMT composite powder could enhance the barrier properties of the EP coating and reduce the corrosion rate of the steel beneath the coating. The coating showed the best corrosion protection performance when 3 per cent PANI/OMMT powder was added to the coating. Originality/value The research clarified the influence of PANI/OMMT content on the corrosion protection of coating from two aspects: one is the barrier performance of the coating; the other is the corrosion inhibitors for metal substrate.

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INVESTIGATION OF CERIUM (III) ACTIVATED-CERIA NANOPARTICLES AS CORROSION INHIBITORS FOR CARBON STEEL

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/56/2/10977 ◽

2018 ◽

Vol 56 (2) ◽

pp. 165

Author(s):

Anh Son Nguyen ◽

Thuy Duong Nguyen ◽

Thu Thuy Thai ◽

Thi Xuan Hang To

Keyword(s):

Carbon Steel ◽

Corrosion Protection ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Salt Spray ◽

Barrier Properties ◽

Ceria Nanoparticles ◽

Nacl Solution ◽

X Ray Diffraction ◽

Transmission Electron

The present work investigated the corrosion protection performance of ions Ce3+ activated-cerium(IV) oxides nanoparticles for carbon steel in a NaCl solution. Ceria nanoparticles were synthesized by homogeneous precipitation in ethanol/water mixed solvent. The obtained CeO2 nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). The corrosion inhibition action of the activated nanoparticles by cerium(III) ions on carbon steel in NaCl solution was evaluated by electrochemical measurements (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization). Then, the effect of cerium salt activated-CeO2 on the protection properties of poly-vinyl-butyral (PVB) coating deposited onto carbon steel plate was studied by salt spray test. The obtained results showed that the salt activated-nanoparticles are anodic corrosion inhibitors. The presence of Ce3+ activated CeO2 in the coating improved the barrier properties and corrosion protection performance of the PVB coating. No swellings of coating were observed after 48 hours of exposure in salt spray chamber.

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EIS study of the corrosion behavior of an organic coating applied on Algerian oil tanker

Metallurgical Research & Technology ◽

10.1051/metal/2020064 ◽

2020 ◽

Vol 117 (6) ◽

pp. 610

Author(s):

Nadia Hammouda ◽

Kamel Belmokre

Keyword(s):

Corrosion Protection ◽

Electrochemical Impedance ◽

Paint Film ◽

Organic Coating ◽

Diffusion Resistance ◽

Double Layer Capacitance ◽

Carbon Steel Surface ◽

Chloride Environment ◽

Oil Tanker ◽

Epoxy Paint

Organic coatings are widely employed in the corrosion protection of most metal surfaces, particularly steel. They provide a barrier against corrosive species present in the environment, due to their high resistance to oxygen, water and ions transport. This study focuses on the evaluation of corrosion protection performance of epoxy paint on the carbon steel surface in chloride environment (3% NaCl) by Electrochemical Impedance Spectroscopy (EIS). The electrochemical behavior of painted surface was estimated by EIS parameters that contained paint film resistance, paint film capacitance and double layer capacitance. On the basis of calculation using EIS spectrums it was observed that pore resistance (Rpore) decreased with the appearance of doubled layer capacitance (Cdl) due to the electrolyte penetration through the film. This was further confirmed by the decrease of diffusion resistance (Rd) which was also the indicator of the deterioration of paint film protectiveness. Microscopic analyses have shown that oxidation dominates the corroded surfaces.

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Design and Multidimensional Screening of Flash-PEO Coatings for Mg in Comparison to Commercial Chromium(VI) Conversion Coating

Metals ◽

10.3390/met11020337 ◽

2021 ◽

Vol 11 (2) ◽

pp. 337

Author(s):

Ewa Wierzbicka ◽

Marta Mohedano ◽

Endzhe Matykina ◽

Raul Arrabal

Keyword(s):

Corrosion Resistance ◽

Corrosion Protection ◽

Electrochemical Impedance ◽

Salt Spray ◽

Conversion Coating ◽

Neutral Salt ◽

Chromium Vi ◽

Alkaline Electrolytes ◽

Az31b Alloy ◽

Plasma Electrolytic

REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations demand for an expedient discovery of a Cr(VI)-free alternative corrosion protection for light alloys even though the green alternatives might never be as cheap as current harmful technologies. In the present work, flash- plasma electrolytic oxidation coatings (FPEO) with the process duration < 90 s are developed on AZ31B alloy in varied mixtures of silicate-, phosphate-, aluminate-, and fluoride-based alkaline electrolytes implementing current density and voltage limits. The overall evaluation of the coatings’ anticorrosion performance (electrochemical impedance spectroscopy (EIS), neutral salt spray test (NSST), paintability) shows that from nine optimized FPEO recipes, two (based on phosphate, fluoride, and aluminate or silicate mixtures) are found to be an adequate substitute for commercially used Cr(VI)-based conversion coating (CCC). The FPEO coatings with the best corrosion resistance consume a very low amount of energy (~1 kW h m−2 µm−1). It is also found that the lower the energy consumption of the FPEO process, the better the corrosion resistance of the resultant coating. The superb corrosion protection and a solid environmentally friendly outlook of PEO-based corrosion protection technology may facilitate the economic justification for industrial end-users of the current-consuming process as a replacement of the electroless CCC process.

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Protection of Carbon Steel Rebars by Epoxy Coating with Smart Environmentally Friendly Microcapsules

Coatings ◽

10.3390/coatings11020113 ◽

2021 ◽

Vol 11 (2) ◽

pp. 113

Author(s):

Jacob Ress ◽

Ulises Martin ◽

Juan Bosch ◽

David M. Bastidas

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Corrosion Protection ◽

Corrosion Potential ◽

Electrochemical Impedance ◽

Pore Solution ◽

Control Sample ◽

Chloride Ions ◽

Epoxy Coating ◽

Transfer Resistance

The protection of mild steel by modified epoxy coating containing colophony microencapsulated corrosion inhibitors was investigated in this study. The corrosion behavior of these epoxy coatings containing colophony microcapsules was studied by electrochemical analysis using cyclic potentiodynamic polarization and electrochemical impedance spectroscopy. The microcapsule coating showed decreased corrosion current densities of 2.75 × 10−8 and 3.21 × 10−8 A/cm2 along with corrosion potential values of 0.349 and 0.392 VSCE for simulated concrete pore solution and deionized water with 3.5 wt.% NaCl, respectively, indicating improved corrosion protection in both alkaline and neutral pH. Electrochemical impedance spectroscopy analysis also showed charge transfer resistance values over one order of magnitude higher than the control sample, corroborating the electrochemical corrosion potential and current density testing results. Overall, the use of colophony microcapsules showed improved corrosion protection in simulated concrete pore solution and DI water solutions containing chloride ions.

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Performance of coatings containing treated silica fume in the corrosion protection of reinforced concrete

Pigment & Resin Technology ◽

10.1108/prt-08-2017-0076 ◽

2018 ◽

Vol 47 (4) ◽

pp. 350-359 ◽

Cited By ~ 4

Author(s):

Nivin M. Ahmed ◽

Mostafa G. Mohamed ◽

Reham H. Tammam ◽

Mohamed R. Mabrouk

Keyword(s):

Reinforced Concrete ◽

Silica Fume ◽

Corrosion Protection ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Dual Function ◽

Core Shell ◽

Protection Efficiency ◽

Content Type ◽

Anticorrosive Pigments

Purpose This study aims to apply novel anticorrosive pigments containing silica fume-phosphates (Si-Ph), which were prepared using core-shell technique by covering 80-90 per cent silica fume (core) with 10-20 per cent phosphates (shell) previously, to play dual functions simultaneously as anticorrosive pigments in coating formulations and as an anticorrosive admixture in concrete even if it is not present in the concrete itself. Two comparisons were held out to show the results of coatings on rebars containing core-shell pigments in concrete, and concrete admixtured with silica fume can perform a dual function as anticorrosive pigment and concrete admixture. The evaluation of corrosion protection efficiency of coatings containing core-shell pigments and those containing phosphates was performed. Design/methodology/approach Simple chemical techniques were used to prepare core-shell pigments, and their characterization was carried out in a previous work. These pigments were incorporated in solvent-based paint formulations based on epoxy resin. Different electrochemical techniques such as open-circuit potential and electrochemical impedance spectroscopy were used to evaluate the anticorrosive efficiency of the new pigments. Findings The electrochemical measurements showed that concrete containing coated rebars with core-shell pigments exhibited almost similar results to that of concrete admixtured with silica fume. Also, the anticorrosive performance of coatings containing Si-Ph pigments offered protection efficiency almost similar to that of phosphates, proving that these new pigments can perform both roles as anticorrosive pigment and concrete admixture. Originality/value Although the new Si-Ph pigments contain more than 80 per cent waste material, its performance can be compared to original phosphate pigments in the reinforced concrete.

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