scholarly journals Corrosion Performance of Cu-Based Coins in Artificial Sweat

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
J. Porcayo-Calderon ◽  
R. A. Rodríguez-Díaz ◽  
E. Porcayo-Palafox ◽  
L. Martinez-Gomez
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Impedance ◽  
Polarization Curves ◽  
Corrosion Mechanism ◽  
Corrosion Performance ◽  
Linear Polarization Resistance ◽  
Artificial Sweat ◽  
Anodic Zone

The performance of different Cu-based coins in artificial sweat was evaluated. The electrochemical behavior of the coins was determined by potentiodynamic polarization curves, linear polarization resistance, and electrochemical impedance spectroscopy. Regardless of the chemical composition of the Cu-based coins, they showed similar polarization curves; particularly, the observed similarity in the anodic zone suggests that the corrosion mechanism is the same in all cases. The presence of Ni and Zn does not appreciably affect the corrosion resistance of Cu. However, the presence of both elements affects the corrosion resistance of Cu. Electrochemical impedance spectroscopy measurements showed the presence of three time constants with very similar characteristics, again indicating that the main corrosion mechanism is the same in all cases. Equivalent circuits confirmed that the corrosion performance of the Ni-Zn-Cu coins depends on the Zn/Ni ratio, such that decreasing this value decreases the corrosion resistance of the alloy. In general, nickel has a detrimental effect due to the formation of highly soluble Ni-based corrosion products.

Effect of Doping of Nanoparticles on the Properties of Zn-Ni Composite Coatings

2018 ◽  
Vol 18 ◽  
pp. 19-26
Author(s):  
Nadjette Belhamra ◽  
Abd Raouf Boulebtina ◽  
Khadidja Belassadi ◽  
Abdelouahed Chala ◽  
Malika Diafi
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Impedance ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Alloy Coating ◽  
Corrosion Performance ◽  
X Ray ◽  
Ni Alloy

The purpose of this paper was to investigate the effect of Al2O3 and TiO2 nanoparticles contents on structural proporties, microhardness and corrosion resistance of Zn-Ni alloy coationg. Zn-Ni, Zn-Ni-Al2O3 and Zn-Ni-TiO2 composite coatings were electrodeposited on steel substrate by direct current in sulphate bath.The structure of the coatings was studied by X-ray diffration and by scaning electron miroscopy. The results showed the appearance of Ni5Zn21 phases and that the incrorporation of Al2O3 and TiO2 in the Zn-Ni coating refined the crystal grain size.The corrosion performance of coating in the 0.6M NaCl as a corrisive solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy EIS methods. It was found that the incorporation of nanoparticules in Zn-Ni alloy coating have better corrosion resistance and the values of Rct and Zw increase, while the values of Cdl decrease with increasing of nanoparticules.

Electrochemical Corrosion Behavior of AZ80 Magnesium Alloy Tube Fabricated by Hydrostatic Extrusion

2014 ◽  
Vol 624 ◽  
pp. 77-81
Author(s):  
Zhi Lin Wu ◽  
Duo Xiang Wu ◽  
Ren Shu Yuan ◽  
Lei Zhao ◽  
Yan Bao Zhao
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Magnesium Alloy ◽  
Impedance Spectroscopy ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Electrochemical Corrosion ◽  
Hydrostatic Extrusion ◽  
Polarization Curves ◽  
Az80 Magnesium Alloy

The corrosion behavior of hydrostatic extruded tube AZ80 magnesium alloy was investigated by polarization curves and electrochemical impedance spectroscopy (EIS) in simulated atmosphere. The results indicated that, the corrosion resistance of the hydrostatic extruded AZ80 magnesium alloy with uneven deformed grains and increased sub-grains were obviously weakened, with larger corrosion current density in the polarization curves and lower corrosion resistances in the electrochemical impedance spectroscopy plots. This was mainly because of the hydrostatic extrusion which made AZ80 magnesium alloy within large numbers of dislocation tangles. So the residual stress increased the electrochemical activity of magnesium alloy which reduced the corrosion resistance of magnesium alloys.

Electrochemical impedance spectroscopy study of CuO and Cu coating systems

2014 ◽  
Vol 43 (6) ◽  
pp. 371-378 ◽  
Author(s):  
N.A. Mat Nor ◽  
L. Ismail ◽  
S.K.M. Jamari ◽  
K. Ramesh ◽  
B. Vengadaesvaran ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Copper Oxide ◽  
Double Layer ◽  
Water Uptake ◽  
Electrochemical Impedance ◽  
Double Layer Capacitance ◽  
Corrosion Performance ◽  
Content Type

Purpose This paper aims to analyse the coating behaviour in corrosion environment as well as to evaluate the best percentage amount of copper oxide and copper needed for organic coating in order to prevent the corrosion degradation. Electrochemical impedance spectroscopy (EIS) studies have been conducted in order to evaluate the corrosion performance of polyester-epoxy-copper oxide and polyester-epoxy-copper coating systems. Design/methodology/approach The availability of this modem instruments is used to obtain impedance data as well as computer programs to interpret the results that made the technique popular. In addition, EIS is well suited to the study of polymer-coated metals. Findings The results showed that samples containing 25 weight per cent of copper oxide and copper (90P25CuO and 90P25Cu) obtained the excellent corrosion properties from the first day up to 30 days of NaCl immersion. The highest corrosion resistance values obtained by 90P25CuO and 90P25Cu on the 30th day were 7.107 × 108 O and 5.701 × 108 O, respectively, with lower double layer capacitance of 1.407 × 10−9 Farad and 3.935 × 10−9 Farad, respectively. Moreover, the water uptake gained by these two coating samples was the lowest at the end of immersion, which was 0.0084 for 90P25CuO and 0.1592 for 90P25Cu, showing that the sample has good corrosion performance. Originality/value This paper discussed on the highest corrosion resistance, double layer capacitance and the water uptake of the copper (Cu) and copper oxide (CuO) coating system obtained from the EIS measurements.

Electrochemical Impedance Spectroscopy (EIS) Study of Nano-Composite Polyurea Coating under the Wet-Dry Cyclic Conditions

2014 ◽  
Vol 789 ◽  
pp. 495-500
Author(s):  
Bing Ying Wang ◽  
Qing Hao Shi ◽  
Wen Long Zhang
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Composite Coating ◽  
Electrochemical Impedance ◽  
Protective Action ◽  
Experimental Result ◽  
Resistance Property ◽  
Corrosion Resistance Property ◽  
Mass Fractions

The polyurea was modified by adding different amounts of nanometer ZnO. The corrosion behavior of polyurea/primer composite coating system in wet-dry cyclic environment of 3.5% NaCl solution was studied by using the Electrochemical Impedance Spectroscopy (EIS) measurement and adhesion test technology. The experimental result showed that, different mass fractions of nanometer ZnO had different influences on the corrosion resistance property of coating. When the mass fraction of nanometer ZnO was 5%, the composite coating had the largest protective action. The corrosion resistance property of nanometer ZnO can be improved by increasing the density of polyurea coating, however, the corrosion resistance property of polyurea coating will be weakened in case of exceeding the critical adding amount.

Synthesis of poly(methylcarbazole) and its nanoclay and nanozinc composites and corrosion protection performances on stainless steel Type 304

2017 ◽  
Vol 24 (6) ◽  
pp. 825-832 ◽  
Author(s):  
Murat Ates
Keyword(s):  
Stainless Steel ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Protection ◽  
Electrochemical Impedance ◽  
Equivalent Circuit Model ◽  
Optical Microscope ◽  
Polarization Curves ◽  
Protective Behavior ◽  
Zn Nanoparticles

AbstractMethylcarbazole (MCz) and its nanocomposites with Montmorillonite nanoclay and Zn nanoparticles were chemically synthesized on a stainless steel (SS304) electrode. The modified electrode was characterized by optical microscope, scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), Fourier-transform infrared spectroscopy-attenuated transmission reflectance (FTIR-ATR), four-point probe, and electrochemical impedance spectroscopy (EIS) analysis. The synthesized stainless steel/poly(methylcarbazole) (SS/P(MCz)), stainless steel/poly(methylcarbazole)/nanoclay (SS/P(MCz)/nanoclay), and stainless steel/poly(methylcarbazole)/nanoZn (SS/P(MCz)/nanoZn) were studied by potentiodynamic polarization curves. The protective behavior of these coatings in 3.5% NaCl as the corrosion medium was investigated using Tafel polarization curves, as well as electrochemical impedance spectroscopy. The corrosion protection parameters were also supported by EIS and an equivalent circuit model of Rs(Qc(Rc(QpRct))). The corrosion current of the SS/P(MCz)/nanoclay samples was found to be much lower (icorr=0.010 μA×cm-2) than that of SS/P(MCz)/nanoZn (icorr=0.031 μA×cm-2) and pure SS/P(MCz) samples. These results reveal that chemically synthesized SS/P(MCz), SS/P(MCz)/nanoclay, and SS/P(MCz)/nanoZn nanocomposite film coating have high corrosion protection efficiency (PE=99.56%, 99.89%, and 99.67%, respectively). Thus, based on the study findings, we posit that nanoclay and Zn nanoparticles possess favorable barrier properties, which can be employed in order to achieve improvements in chemical corrosion protection through P(MCz) coating.

The effect of electroplating current density on microstructure, corrosion, and wear behavior of Ni–P–W–TiO2 coating

2021 ◽  
Vol 112 (6) ◽  
pp. 474-485
Author(s):  
Sajjad Sadeghi ◽  
Hadi Ebrahimifar
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Current Density ◽  
Potentiodynamic Polarization ◽  
Electrochemical Impedance ◽  
Wear Behavior ◽  
Micro Hardness ◽  
Aisi 304L

Abstract The use of ceramic particles in the matrix of alloy coatings during the electroplating process has received considerable attention. These particles can create properties such as high corrosion resistance, insolubility, high-temperature stability, strong hardness, and self-lubrication capability. Herein, an Ni–P–W–TiO2 coating was deposited on an AISI 304L steel substrate using the electroplating method. Electroplating was performed at current densities of 10, 15, 20, and 25 mA · cm–2, and the effect of current density on microstructure, corrosion behavior, and wear behavior was investigated. The coatings were characterized by means of scanning electron microscopy. To investigate corrosion resistance, potentiodynamic polarization and electrochemical impedance spectroscopy tests were performed in a 3.5% NaCl aqueous solution. A pin-on-disk test was conducted to test the wear resistance of uncoated and coated samples. Sample micro-hardness was also measured by Vickers hardness testing. Examination of the microstructure revealed that the best coating was produced at a current density of 20 mA · cm–2. The results of potentiodynamic polarization and electrochemical impedance spectroscopy tests were consistent with microscopic images. The coating created at the current density of 20 mA · cm–2 had the highest corrosion resistance compared to other coated and non-coated samples. Furthermore, the results of the wear test showed that increasing the current density of the electroplating path up to 20 mA · cm–2 enhances micro-hardness and wear resistance.

scholarly journals On the corrosion mechanism of Mg investigated by electrochemical impedance spectroscopy

2019 ◽  
Vol 306 ◽  
pp. 61-70 ◽  
Author(s):  
Maurilio Pereira Gomes ◽  
Isolda Costa ◽  
Nadine Pébère ◽  
Jesualdo Luiz Rossi ◽  
Bernard Tribollet ◽  
...  
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Impedance ◽  
Corrosion Mechanism

scholarly journals Electrochemical Behavior of Conventional and Rheo-High-Pressure Die Cast Low Silicon Aluminum Alloys in NaCl Solutions

CORROSION ◽  
10.5006/3254 ◽  
2019 ◽  
Vol 75 (11) ◽  
pp. 1339-1353
Author(s):  
Maryam Eslami ◽  
Flavio Deflorian ◽  
Caterina Zanella
Keyword(s):  
High Pressure ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Behavior ◽  
Anodic Polarization ◽  
Electrochemical Impedance ◽  
Casting Process ◽  
Corrosion Mechanism ◽  
Die Cast ◽  
Polarization Test

The electrochemical behavior of a low silicon aluminum alloy cast by the conventional and rheo-high-pressure die cast processes is evaluated using polarization test and electrochemical impedance spectroscopy in 0.01 M, 0.05 M, 0.1 M, and 0.6 M sodium chloride solutions. Compared to the conventional high-pressure die cast process, rheocasting introduces some alterations in the microstructure including the presence of aluminum grains with different sizes, formed at different solidification stages. According to the results of the anodic polarization test, conventional cast and rheocast samples show similar breakdown potentials. However, the rheocast samples present enhanced oxygen reduction kinetics compared to the conventional cast sample. Based on scanning electron microscopy examinations, localized microgalvanic corrosion is the main corrosion mechanism for both alloys and it initiates at the interface of aluminum with iron-rich intermetallic particles which are located inside the eutectic regions. The corrosion further develops into the eutectic area. Although the rate of the cathodic reaction can be influenced by the semisolid microstructure, according to the results of anodic polarization and electrochemical impedance spectroscopy tests, the corrosion behavior is not meaningfully affected by the casting process.

Corrosion Resistance of a New Cu-Alloy (Low Ni) vis-à-vis Cu-10Ni Alloy in Sulfide Polluted Synthetic Seawater

2012 ◽  
Vol 585 ◽  
pp. 488-492
Author(s):  
Adeeba F. Khan ◽  
Awanikumar P. Patil ◽  
T. Subba Rao
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Impedance ◽  
Accelerated Corrosion ◽  
Synthetic Seawater ◽  
Cu Alloy

Cu-10Ni alloy suffers accelerated corrosion in sulfide polluted seawater. As an alternative, a new single phased, Cu-28%Zn-5%Ni-5%Mn-2%Fe alloy (hereby referred as CNZ-alloy) is developed and tested for the corrosion resistance in clean and sulfide polluted synthetic seawater. The CNZ-alloy showed better corrosion resistance than the standard Cu-10Ni alloy in both the test solutions i.e. clean and sulfide polluted synthetic seawater with . The results are discussed on the basis of polarization and electrochemical impedance spectroscopy. The better corrosion resistance of CNZ-alloy is attributed to the formation of protective ZnS and MnS2 films.

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