scholarly journals Investigation of Passive Film Properties and Pitting Resistance of AISI 316 in Aqueous Ethanoic Acid Containing Chloride Ions using Electrochemical Impedance Spectroscopy(EIS)

2011 ◽  
Vol 29 (4) ◽  
pp. 233-251 ◽  
Author(s):  
N Mahato ◽  
M M Singh
2020 ◽  
Vol MA2020-02 (12) ◽  
pp. 1296-1296
Author(s):  
Adrien Barroux ◽  
Nadège Ducommun ◽  
Eric Nivet ◽  
Julien Delgado ◽  
Bernard Tribollet ◽  
...  

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 113
Author(s):  
Jacob Ress ◽  
Ulises Martin ◽  
Juan Bosch ◽  
David M. Bastidas

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.


2020 ◽  
Vol 1 (1) ◽  
pp. 77-91 ◽  
Author(s):  
Ingmar Bösing ◽  
Georg Marquardt ◽  
Jorg Thöming

Martensitic stainless steels are widely used materials. Their mechanical and corrosion properties are strongly influenced by their microstructure and thereby can be affected by heat treatment. In the present study, the effect of different austenitizing temperatures on the passive film growth kinetics of martensitic stainless steel is studied by electrochemical impedance spectroscopy. The data was further fitted by the point defect model to determine kinetic parameters. We show that an increasing austenitizing temperature leads to a more protective passive film and slows down passive film dissolution in sulfuric acid.


2011 ◽  
Vol 250-253 ◽  
pp. 222-227 ◽  
Author(s):  
Bi Lan Lin ◽  
Yu Ye Xu

Galvanizing on the surface of reinforcing steel is an effective measure to control corrosion of reinforcing concrete structures. The corrosion behaviors of hot-dip galvanized (HDG) reinforcing steel in simulated concrete pore solution (SCP solution) with various pH and chlodride values were investigated using electrochemical impedance spectroscopy (EIS). Two equivalent circuit models corresponding to the corrosion process were proposed and the evolution feature of the corrosion parameters were analyzed. The results show that when the SCP solution was carbonated seriously (pH<11), there is hydrogen evolution phenomenon and the corrosion resistance of HDG reinforcing steel is decreased. A minute carbonation of SCP solution (11.5≤pH<12.5) favors the further passivation of the zinc layer and the corrosion resistance is enhanced. The corrosion rate of HDG reinforcing steel at pH=12.0 is minimal, around 0.59 μm/year, whereas that at pH=12.5 is approximate 1.21 μm/year. In the conditions of pH=12.5 and NaCl concentration no more than 0.5wt.%, the corrosion resistance of the passivation film on HDG reinforcing steel is good. In a serious carbonation case, the corrosion rate is increased greatly with chloride ions.


CORROSION ◽  
10.5006/2680 ◽  
2018 ◽  
Vol 74 (6) ◽  
pp. 705-714 ◽  
Author(s):  
Yingying Yue ◽  
Chengjun Liu ◽  
Edouard Asselin ◽  
Peiyang Shi ◽  
Maofa Jiang

H2SO4-H2O2 mixtures are a promising and environmentally friendly passivation medium for the stainless-steel pickling process. The corrosion behavior of stainless steel is highly dependent on the kinetics of passive film growth. Long-term electrochemical measurements, including polarization resistance, open circuit potential (OCP), and electrochemical impedance spectroscopy (EIS) measurements were performed to investigate the evolution of the passive state of 304 stainless steel. According to the OCP results, an active-passive transition takes place in 10 ks in 0.5 M H2SO4 solution containing 0.005 M to 0.3 M H2O2. Polarization resistance results indicate that the passive film thickness keeps growing after OCP stabilization in the presence of H2O2. Electrochemical impedance spectroscopy (EIS) results confirmed that the growth of the passive film in H2SO4-H2O2 solutions takes about 9 h. Additionally, according to the Point Defect Model (PDM) and Mott–Schottky analysis, the semiconductor properties of the passive film on 304 stainless steel in H2SO4-H2O2 solution were studied. The results indicate that the passive film is an n-type semiconductor. The donor density is in the range of 1.6 × 10−21 cm−3 to 24 and decreases exponentially with increasing film formation potential (this potential coincides with the final OCP in the corresponding H2SO4-H2O2 solutions). By postulating that most donors are oxygen vacancies, the point defect properties including diffusivity and electrical field strength are obtained.


Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5508
Author(s):  
JangHyun Park ◽  
MyeongGyu Jung

In this study, the effect of NaCl and LiNO2 content on the deterioration of embedded rebars in concrete due to corrosion was examined by measuring the natural potential and impedance. Wet–dry cycles were performed to accelerate the corrosion of embedded rebars in reinforced concrete, following which the potential and impedance corresponding to the cycles were measured. For the reinforced concrete containing only NaCl, the passive film of the embedded rebar surfaces deteriorated after two weeks of accelerated corrosion, and its polarization resistance decreased. When 0.6 M LiNO2 per NaCl was added, the reinforced concrete deteriorated at the same rate as the normal embedded rebars, and the polarization resistance was higher than the initial values. When 1.2 M LiNO2 per NaCl was added, the passive film of the embedded rebars remained intact even after 10 weeks of accelerated corrosion, protecting the rebars from deterioration.


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