Utilization of Electrochemical Impedance Techniques to Estimate Corrosion Damage of Steel Infrastructures

2009 ◽  
pp. 155-155-15
Author(s):  
K Homma ◽  
N Goto ◽  
K Matsuoka ◽  
S Ito
Keyword(s):  
Electrochemical Impedance ◽  
Corrosion Damage

Study of Corrosion Damage Under Protective Coatings

2001 ◽  
Author(s):  
Mohammad Khobaib ◽  
Jochen Hoffmann ◽  
Shamachary Sathish ◽  
Michael S. Donley
Keyword(s):  
Spatial Resolution ◽  
Electrochemical Impedance ◽  
Protective Coatings ◽  
Salt Spray ◽  
Electrochemical Techniques ◽  
Corrosion Damage ◽  
Acoustic Microscopy ◽  
Localized Corrosion ◽  
Corrosion Activity ◽  
Military Aircraft

Abstract Polymer coatings provide an excellent corrosion barrier for Al-skinned military aircraft. However, the degradation and damage of the coatings in their service life over time leads to the initiation of corrosion damage at the substrate level. Early detection and negation of such activity can provide extensive cost savings. Several Electrochemical techniques and Non Destructive Evaluation (NDE) show promise in detecting the onset of corrosion under such coatings. Current accelerated testing of aircraft coating systems for corrosion protection relies heavily on salt spray methods. Electrochemical techniques such as Electrochemical Impedance Spectroscopy (EIS) and Electrochemical Noise Methods (ENM) provide insight into the global properties of a coating system, and both techniques are being used on a limited basis. However, there is a need to investigate corrosion events with greater spatial resolution under coatings at the metal/coating interface. Such corrosion activity may be related to coating defects and variations in the surface chemistry of the underlying metal. The Scanning Vibrating Electrode Technique (SVET) has been developed to allow the investigation of localized corrosion activity with high spatial resolution. Such activity may be associated with coating defects or galvanic coupled regions of the metal surface. Electrochemical and NDE techniques were used to investigate the early stage of corrosion activity under protective coatings. Coatings in this investigation ranged from a simple epoxy amine to commercially used military aircraft polyurethane coatings. SVET testing of panels with intact high-resistance barrier coatings could not reveal corrosion damage under normal testing conditions because of little or no corrosion activity within the limited exposure time. Chemical, mechanical, and electrochemical means of accelerating the corrosion damage were utilized to obtain results in a reasonable time frame. Corrosion initiation and its progress under the coating were studied in detail and the results are discussed here. Complimentary high-resolution NDE techniques, such as Scanning Acoustic Microscopy (SAM) and Fan Thermography measurements were used to identify the corrosion sites. The overall objective of this investigation is to establish a correlation between the electrochemical and NDE techniques.

Correlation of Acoustic Emission and Corrosion Resistance of Lacquer Coatings on Tin-Free Steel

2015 ◽  
Vol 659 ◽  
pp. 628-632
Author(s):  
Pornsak Srisungsitthisunti ◽  
Siriporn Daopiset ◽  
Noparat Kanjanaprayut
Keyword(s):  
Acoustic Emission ◽  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Corrosion Damage ◽  
Corrosion Monitoring ◽  
Metallic Structures ◽  
Crack Monitoring ◽  
Before And After ◽  
Non Destructive

Acoustic emission (AE) is a non-destructive technique which is well known for crack monitoring. Moreover, it has been widely used for corrosion and erosion damage on metallic structures. In this study, AE technique was applied for quick monitoring of corrosion resistance of lacquer coatings on tin free steel and laminated steel for food can-packaging. There were three types of coatings: (A) BPA-NI lacquer, (B) BPA-complied lacquer, and (C) PET lamination. These coatings were investigated in flat-sheet and in deformed sheet. Cathodic disbonding (CD) technique was carried out to cause separation between the coating and the metal substrate and initialize corrosion damage. AE signals was detected immediately with potential excitation, and showed good correlation with coating corrosion resistance during corrosion development. AE count signal matched with resulting current during CD, and proportional to corroded areas. In addition, coatings properties were measured before and after the CD process by electrochemical impedance spectroscopy (EIS). A combination of AE and CD techniques offers an in-situ non-destructive corrosion monitoring of coating quality before and during delamination development, and useful for can-packaging testing.

scholarly journals Corrosion inhibition of austenitic stainless steel by clay in polluted phosphoric acid with presence of SiC abrasif

2018 ◽  
Vol 149 ◽  
pp. 01049 ◽  
Author(s):  
S. Skal ◽  
Y. Kerroum ◽  
Y. El Aoufir ◽  
A. Guenbour ◽  
A. Bellaouchou ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Phosphoric Acid ◽  
Electrochemical Impedance ◽  
Protective Layer ◽  
Corrosion Damage ◽  
Electrochemical Process ◽  
Solid Particles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Corrosive Environments

Stainless steels have many properties mechanical and chemical resistances resulting from the formation of the protective layer (passive film) on their surface which prevents the metal to react with corrosive environments such as, phosphoric acid. This acid contains various impurities, including agressive agents and solid particles of gypsum, increase the risk of corrosion damage depending on the type of stainless steel used. In addition, it has been show that abrasion-corrosion causes an acceleration electrochemical process leading to a decrease in the resistance of materials. This work is to find a solution through an ecological inhibitor. That why we have been studied the effect of crude clay on corrosion behavior of Alloy 31 in polluted phosphoric acid with abrasive by electrochemical impedance spectroscopy (EIS) . The clay was characterized by X-ray fluorescence spectroscopy (FX), X-ray diffraction (DRX) and infrared spectroscopy (IR). EIS exhibited that resistance of Alloy 31 increased with increase the concentration of inhibitor.

scholarly journals Characterizing Steel Corrosion in Different Alkali-Activated Mortars

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7366
Author(s):  
Nina Gartner ◽  
Miha Hren ◽  
Tadeja Kosec ◽  
Andraž Legat
Keyword(s):  
Electrochemical Impedance ◽  
Steel Corrosion ◽  
Corrosion Damage ◽  
Corrosion Properties ◽  
Reinforcing Bar ◽  
Wide Range ◽  
Steel Bars ◽  
Computed Microtomography ◽  
Eis Measurements ◽  
Alkali Activated

Alkali-activated materials (AAMs) present a promising potential alternative to ordinary Portland cement (OPC). The service life of reinforced concrete structures depends greatly on the corrosion resistance of the steel used for reinforcement. Due to the wide range and diverse properties of AAMs, the corrosion processes of steel in these materials is still relatively unknown. Three different alkali-activated mortar mixes, based on fly ash, slag, or metakaolin, were prepared for this research. An ordinary carbon-steel reinforcing bar was installed in each of the mortar mixes. In order to study the corrosion properties of steel in the selected mortars, the specimens were exposed to a saline solution in wet/dry cycles for 17 weeks, and periodic electrochemical impedance spectroscopy (EIS) measurements were performed. The propagation of corrosion damage on the embedded steel bars was followed using X-ray computed microtomography (mXCT). Periodic EIS measurements of the AAMs showed different impedance response in individual AAMs. Moreover, these impedance responses also changed over the time of exposure. Interpretation of the results was based on visual and numerical analysis of the corrosion damages obtained by mXCT, which confirmed corrosion damage of varying type and extent on steel bars embedded in the tested AAMs.

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

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.

Experimental and Theoretical Comparable Study of Pure and Zinc Porphyrin Surface Modified ZnO Nanorod Arrays for Hybrid Solar Cell Applications

2020 ◽  
pp. 114-119
Keyword(s):  
Solar Cell ◽  
Electrochemical Impedance ◽  
Hybrid Solar Cell ◽  
Cell Performance ◽  
Solar Cell Performance ◽  
Solar Cell Efficiency ◽  
Cell Efficiency ◽  
Annealing Effects ◽  
Vertically Aligned ◽  
Surface Modified

Experimental and theoretical study Porphyrin-grafted ZnO nanowire arrays were investigated for organic/inorganic hybrid solar cell applications. Two types of porphyrin – Tetra (4-carboxyphenyle) TCPP and meso-Tetraphenylporphine (Zinc-TPP)were used to modify the nanowire surfaces. The vertically aligned nanowires with porphyrin modifications were embedded in graphene-enriched poly (3-hexylthiophene) [G-P3HT] for p-n junction nanowire solar cells. Surface grafting of ZnO nanowires was found to improve the solar cell efficiency. There are different effect for the two types of porphyrin as results of Zn existing. Annealing effects on the solar cell performance were investigated by heating the devices up to 225 °C in air. It was found that the cell performance was significantly degraded after annealing. The degradation was attributed to the polymer structural change at high temperature as evidenced by electrochemical impedance spectroscopy measurements.

Sign in / Sign up

Export Citation Format

Share Document