The Corrosion Features of Q235B Steel under Immersion Test and Electrochemical Measurements in Desulfurization Solution

With the continuous tightening marine diesel engines emission standards, removing sulfur oxides (SOX) by sodium hydroxide solution absorption is a highly efficiency and economic method, which has been a hot area of research. The ensuing desulfurization solution is a new corrosive system, the aim of this paper is to ascertain the corrosion feature of Q235B steel in desulfurization solution, which lays a theoretical foundation for industrialization. For this purpose, mass loss, electrochemical techniques and surface analyses were applied. The results of mass loss highlight a reduction in the corrosion rate with 35 days of immersion. Higher exposure time increased the compactness of the corrosion product layer and changed phase composition. These conclusions are supported by surface analyses, such as X-ray diffraction and scanning electron microscope. However, electrochemical results showed that the polarization resistance Rp was fluctuant. Both of Rp and charge transfer resistance Rt reach a maximum after immersing 21 days. In addition, although the sediments attached to the steel surface could inhibit corrosion, pitting corrosion aggravated by hydrolyzation of FeSO4 should be given more attention.

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Synergistic Effect of Iodide Ion and 4-Hydroxy Coumarin on the Corrosion Inhibition of Mild Steel in Hydrochloric Acid

ISRN Corrosion ◽

10.1155/2013/184787 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Shyamala R. Krishnamurthy ◽

Meenakshi H. N. Parameswaran

Keyword(s):

Hydrochloric Acid ◽

Mild Steel ◽

Mass Loss ◽

Corrosion Inhibition ◽

Electrochemical Techniques ◽

Corrosion Current ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Hydroxy Coumarin ◽

Loss Method

No discussion of the use of inhibitors in acid solution is complete without mentioning the phenomenon of synergism. Synergism also operates in corrosion protection where an enhanced inhibition may be related to interaction between inhibitor compounds. This effect has been observed since the earlier days of inhibitor technology and continues to be a potent tool in the development of acid inhibitors for specialized uses. Hence, in this paper, the corrosion inhibition behavior of mild steel (MS) in 1 M hydrochloric acid in the presence of 4-hydroxy coumarin (4HC) and potassium iodide (KI) has been investigated using the mass loss method and electrochemical techniques. The inhibitive performance of 4HC is considerably enhanced by the addition of KI. The addition of KI to different concentrations of 4HC has intensified its efficiency through considerable reduction in the mass loss, corrosion current density , double layer capacitance , and increase in charge transfer resistance . The calculated synergism parameter “” is greater than unity, thereby proving the fact that the improvement in inhibition efficiency of 4HC, generated by the addition of KI, is due to synergism.

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Effect of Zirconium Oxide Reinforcement on Microstructural, Electrochemical and Mechanical Properties of TiNi Alloy Produced Via Powder Metallurgy Route

Journal of Engineering Materials and Technology ◽

10.1115/1.4051308 ◽

2021 ◽

pp. 1-22

Author(s):

Syed Abbas Raza ◽

Muhammad Imran Khan ◽

Muhammad Ramzan Abdul karim ◽

Rashid Ali ◽

Muhammad Umair Naseer ◽

...

Keyword(s):

Electrochemical Impedance ◽

Passive Layer ◽

Charge Transfer Resistance ◽

Tini Alloy ◽

X Ray Diffraction ◽

Zro2 Content ◽

Transfer Resistance ◽

X Ray ◽

Conventional Sintering ◽

Layer Resistance

Abstract Equiatomic TiNi alloy composites, reinforced with 0, 5, 10 and 15 vol. % ZrO2, were synthesized using conventional sintering approach. Equiatomic TiNi pre-alloyed powder and ZrO2 powder were mixed in planetary ball mill for 6 hours followed by cold compaction and pressure-less sintering, respectively. The sintered density was found to vary inversely with the addition of ZrO2 content. The X-Ray diffraction spectra have shown the formation of multiple-phases which were resulted from the decomposition of the B19'and B2 phases of the equiatomic TiNi alloy due to the addition of ZrO2 and higher diffusion rate of Ni than that of Ti in the alloy composite. An increase in hardness was noted due to the addition of ZrO2, measured by micro and nanoindentation techniques. Potentiodynamic polarization scan revealed a 10% decrease in the corrosion rate of the composite containing 10 vol. % ZrO2. Electrochemical impedance spectroscopy results indicated an increase in passive layer resistance (Rcoat) due to the increase in charge transfer resistance (Rct) caused by the reduced leaching of ions from the surface.

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The Effect of Achyranthes aspera Extracts on Mild Steel Corrosion in Industrial Water Medium

ISRN Corrosion ◽

10.1155/2013/261847 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Chikkur B. Pradeep Kumar ◽

Kikkeri N. Mohana

Keyword(s):

Mild Steel ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Steel Corrosion ◽

Charge Transfer Resistance ◽

Water Medium ◽

Industrial Water ◽

Transfer Resistance ◽

Achyranthes Aspera ◽

Eis Measurements

Achyranthes aspera (AA) extracts were studied as corrosion inhibitor for mild steel (MS) in industrial water medium using mass loss and electrochemical techniques. The results of the study revealed that AA extracts inhibit MS corrosion through adsorption process following Langmuir adsorption isotherm model. The protection efficiency increased with increase in inhibitor concentration and decreased with temperature. The electrochemical impedance spectroscopy (EIS) measurements showed that the charge transfer resistance increases with increase in the concentration of AA extracts. The polarization curves obtained indicate that AA extracts act as mixed type of inhibitor. Scanning electron microscopy (SEM) was used to analyze the surface adsorbed film.

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PREPARATION AND INVESTIGATION OF ELECTRODEPOSITED Ni–NANO-Cr2O3 COMPOSITE COATINGS

Surface Review and Letters ◽

10.1142/s0218625x15501115 ◽

2016 ◽

Vol 23 (02) ◽

pp. 1550111 ◽

Cited By ~ 3

Author(s):

JIBO JIANG ◽

CHENQI FENG ◽

WEI QIAN ◽

LIBIN YU ◽

FENGYING YE ◽

...

Keyword(s):

Electrochemical Impedance ◽

Composite Coatings ◽

Charge Transfer Resistance ◽

X Ray Diffraction ◽

Transfer Resistance ◽

X Ray ◽

Potentiodynamic Polarization Curves ◽

Nucleation Sites ◽

Passive Transition ◽

Steel Surfaces

The electrodeposition of Ni–nano-Cr2O3 composite coatings was studied in electrolyte containing different contents of Cr2O3 nanoparticles (Cr2O3 NPs) on mild steel surfaces. Some techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness, the potentiodynamic polarization curves (Tafel) and electrochemical impedance spectroscopy (EIS) were used to compare pure Ni coatings and Ni–nano-Cr2O3 composite coatings. The results show that the incorporation of Cr2O3 NPs resulted in an increase of hardness and corrosion resistance, and the maximum microhardness of Ni-nano-Cr2O3 composite coatings reaches about 495 HV. The coatings exhibit an active-passive transition and relatively large impedance values. Moreover, the effect of Cr2O3 NPs on Ni electrocrystallization is also investigated by cyclic voltammetry (CV) and EIS spectroscopy, which demonstrates that the nature of Ni-based composite coatings changes attributes to Cr2O3 NPs by offering more nucleation sites and less charge transfer resistance.

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Electrochemical Hydrogen Evolution over Hydrothermally Synthesized Re-Doped MoS2 Flower-Like Microspheres

Molecules ◽

10.3390/molecules24244631 ◽

2019 ◽

Vol 24 (24) ◽

pp. 4631 ◽

Cited By ~ 3

Author(s):

Juan Aliaga ◽

Pablo Vera ◽

Juan Araya ◽

Luis Ballesteros ◽

Julio Urzúa ◽

...

Keyword(s):

Electron Microscopy ◽

Hydrogen Evolution ◽

Photoelectron Spectroscopy ◽

Charge Transfer Resistance ◽

Chemical Analyses ◽

X Ray Diffraction ◽

Transfer Resistance ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

In this research, we report a simple hydrothermal synthesis to prepare rhenium (Re)- doped MoS2 flower-like microspheres and the tuning of their structural, electronic, and electrocatalytic properties by modulating the insertion of Re. The obtained compounds were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Structural, morphological, and chemical analyses confirmed the synthesis of poorly crystalline Re-doped MoS2 flower-like microspheres composed of few stacked layers. They exhibit enhanced hydrogen evolution reaction (HER) performance with low overpotential of 210 mV at current density of 10 mA/cm2, with a small Tafel slope of 78 mV/dec. The enhanced catalytic HER performance can be ascribed to activation of MoS2 basal planes and by reduction in charge transfer resistance during HER upon doping.

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PREPARATION AND CHARACTERIZATION OF A POLY(PYRROLYL METHANE)/MULTIWALLED CARBON NANOTUBES COMPOSITES

NANO ◽

10.1142/s179329201350063x ◽

2013 ◽

Vol 08 (06) ◽

pp. 1350063

Author(s):

JINXIAN LIN ◽

PAN WANG ◽

YUYING ZHENG

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Multiwalled Carbon Nanotubes ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

Electrode System ◽

X Ray Diffraction ◽

Multiwalled Carbon ◽

Transfer Resistance ◽

Transmission Electron

A poly(pyrrolyl methane) (Poly[pyrrole-2, 5-diyl(4-methoxybenzylidane)], PPDMOBA)/multiwalled carbon nanotubes (MWNTs) composites are fabricated by in situ chemical polycondensation of pyrrole and 4-methoxybenzaldehyde on MWNTs. The structure, morphology, thermal stability and electrical property of the resulting composites are investigated via fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and a four-probe method. The electrochemical performance of the composites is determined in a three-electrode system using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) techniques. FTIR, FESEM and TEM confirm that the composites have been successfully prepared, and PPDMOBA is uniformly dispersed in MWNTs. Electrical conductivity of PPDMOBA/MWNTs composites is 1.39 S cm-1, which is significantly larger than that of pristine PPDMOBA. The specific capacitance and charge transfer resistance of the composites is 56 F g-1 (1 mA cm-2) and 0.3Ω, respectively.

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Electrochemical Study of the Protective Characteristics of CO2 Corrosion Product Layers for Steels API X80 and P110

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.830.139 ◽

2016 ◽

Vol 830 ◽

pp. 139-146

Author(s):

Andrea H. Rojas ◽

Adriana Forero Ballesteros ◽

I.S. Bott

Keyword(s):

Corrosion Rate ◽

Corrosion Product ◽

Oil And Gas ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Morphological Characterization ◽

Product Layer ◽

X Ray Diffraction ◽

Energy Dispersion Spectroscopy ◽

Different Temperatures

This work evaluate the protective characteristic of the CO2 corrosion product layers formed on the surface of two types of steels, API 5L X80 used for transportation of oil and gas, and API 5CT P110 used for case tubing and pipe for oil drilling.Electrochemistry evaluations and morphological characterization of the obtained layer were performed. These steels were exposed to a brine solution containing 3% wt of NaCl, in a pressurized autoclave with 55 bar of CO2 and total pressure of 75 bar at different temperatures (25, 50 and 75°C) and immersion times (7, 15, 21 and 30 days). The corrosion rate was determined by mass loss tests and electrochemical techniques, such as Linear Polarization Resistance and Electrochemical Impedance Spectroscopy. Characteristics of the corrosion product layer such as thickness, morphology, and chemical composition were analyzed by scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS) and X-Ray diffraction (XRD). The corrosion rate decreases with the increase of the immersion time and temperature, and the lower rate of corrosion was obtained for 75°C after 30 days of immersion, for both steels

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Inhibitive Action of Artemisia Plant Extract on the Copper Corrosion in Phosphoric Acid.

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v8i3.6610 ◽

2014 ◽

Vol 8 (3) ◽

pp. 1692-1699

Author(s):

F Mounir ◽

S El Issami ◽

Lh. Bazzi

Keyword(s):

Plant Extract ◽

Potentiodynamic Polarization ◽

Electrochemical Techniques ◽

Gravimetric Method ◽

Charge Transfer Resistance ◽

Copper Corrosion ◽

Transfer Resistance ◽

Impedance Measurements ◽

Polarization Impedance ◽

Inhibitive Action

Effect of Artemisia plant Extract (APE) on the copper corrosion as a corrosion inhibitor in an aerated acidic solution of in 2M H3PO4 containing 3.10-1 M NaCl has been investigated using gravimetric and electrochemical techniques. A significant decrease in the corrosion rate of copper was observed in the presence of the Artemisia plant extract. The potentiodynamic polarization data indicated that the inhibitor was of mixed type. Impedance measurements showed that the charge transfer resistance increased and double layer capacitance decreased with increase in the inhibitor’s concentration. Also, some thermodynamic data for the activation are calculated and discussed. The results obtained from potentiodynamic polarization, impedance measurements and gravimetric method are in good agreement.

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Preparation and electrochemical characterization of PANI/MnCo2O4 nanocomposite as supercapacitor electrode material

Canadian Journal of Chemistry ◽

10.1139/cjc-2017-0423 ◽

2018 ◽

Vol 96 (5) ◽

pp. 477-483 ◽

Cited By ~ 3

Author(s):

Saeid Panahi ◽

Moosa Es’haghi

Keyword(s):

Specific Capacitance ◽

Surface Characterization ◽

Electrochemical Impedance ◽

Rate Capability ◽

Cycling Performance ◽

Charge Transfer Resistance ◽

X Ray Diffraction ◽

Supercapacitor Electrode ◽

Transfer Resistance

In this work, PANI/MnCo2O4 nanocomposite was prepared via in-situ chemical polymerization method. Materials synthesized were characterized by FTIR spectroscopy, X-ray diffraction, and scanning electron spectroscopy. In addition, surface characterization of samples such as specific surface area, pore volume, and pore size distribution was studied. Supercapacitor capability of materials was investigated in 1 mol L–1 Na2SO4 solution using cyclic voltammetry in different potential scan rates and electrochemical impedance spectroscopy (EIS). The specific capacitance of materials was calculated, and it was observed that the specific capacitance of PANI/MnCo2O4 nanocomposite was 185 F g−1, much larger than PANI. Moreover, the prepared nanocomposite exhibited better rate capability in scan rate of 100 mV s−1 with respect to PANI. The EIS experiments revealed that the nanocomposite has lower charge transfer resistance compared with pure PANI. Subsequently, it was shown that the nanocomposite cycling performance was superior to the PANI cycling performance.

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STUDY OF ZN-NI ALLOY COATINGSMODIFIED BY NANO-AL2O3 PARTICLES INCORPORATION

Acta Metallurgica Slovaca ◽

10.12776/ams.v22i3.706 ◽

2016 ◽

Vol 22 (3) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

Malika Diafi ◽

Said Benramache ◽

Elhachmi Guettaf Temam ◽

Adaika Mohamed Lakhdar ◽

Brahim Gasmi

Keyword(s):

Electrochemical Impedance ◽

Research Work ◽

Charge Transfer Resistance ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

Corrosion Properties ◽

Transfer Resistance ◽

Characterization Methods ◽

Ni Alloy ◽

Steel Substrates

AbstractThe aim of this research work was to codeposit nano-Al2O3 particles into Zn-Ni alloy coatings in order to improve some surface ,properties, the influence of the concentration of Al2O3 is the principal object in order to improve the corrosion resistance of the deposit, which has been made by electroplating on steel substrates previously treated, have been studied by several characterization methods, as the X-ray diffraction, measurement of micro hardness and scanning electron microscopy (SEM), protection against corrosion properties studied in a solution of 3% NaCl in the potentiodynamic polarization measurements (Tafel), electrochemical impedance spectroscopy (EIS) to the potential of corrosion free. The parameters that characterize the corrosion behavior can be determined from the plots and Nyquist plots and chronopotentiometry. Trends of increasing the charge transfer resistance and the decrease of capacitance values. XRD and SEM results and identify any coatings Zn-Ni and Zn-Ni-Al2O3 alloy composition have similar phase ( γ-phase structure) and the addition of Al2O3 in the Zn-Ni matrix increases the microhardness, and we note the maximum hardness is obtained for 50 g/L Al2O3.

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