scholarly journals A Measuring Approach to Assess the Corrosion Rate of Magnesium Alloys Using Electrochemical Impedance Spectroscopy

10.5772/65018 ◽  
2017 ◽  
Author(s):  
Maria C. Delgado ◽  
Federico R. García-Galvan ◽  
Violeta Barranco ◽  
Sebastian Feliu Batlle
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Magnesium Alloys ◽  
Electrochemical Impedance

Preparation and Characterization of Polylactic Acid Coating on the Surface of Magnesium Alloy

2015 ◽  
Vol 814 ◽  
pp. 132-136 ◽  
Author(s):  
Xian Yang Hua ◽  
Mei Feng He ◽  
Xiao Qin Zhou
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Magnesium Alloy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Polylactic Acid ◽  
Magnesium Alloys ◽  
Electrochemical Impedance ◽  
Hank’S Solution ◽  
Acid Coating

Magnesium is one of the elements necessary for the body, is the man behind the body’s content of potassium ions within the cell are involved in a series of metabolic processes in vivo, including the formation of bone cells , acceleration of bone healing ability. Resulting from the good mechanical properties and biocompatibility, magnesium alloy is used in medical intervention material, but the high corrosion rate of magnesium alloys is the main drawback to their widespread use, especially in biomedical applications. There is a need for developing new coatings that provide simultaneously corrosion resistance and enhanced biocompatibility. In this work the medical magnesium alloy surface are dipped and coated with polylactic acid, so that obtain a dense uniform polylactic acid coating. And the corrosion resistance of the coating is studied in order to obtain controlled degradable and corrosion resisted magnesium alloy biological material. This paper mainly studies the influence of different concentrations of polylactic acid coating on AZ91D magnesium alloy corrosion resistance. The coated samples were immersed in Hank’s solution and the coating performance was studied by electrochemical impedance spectroscopy and scanning electron microscopy. This research is about the influence of the coating on the corrosion resistance of magnesium alloy through the open circuit potential, polarization curves, electrochemical impedance spectroscopy and Mott-Schottky. The results confirmed that the polylactic acid slow down the corrosion rate of AZ91D magnesium alloys in Hank’s solution. And along with the increase of poly lactic acid concentration, the corrosion resistance of magnesium alloys is improved. There is a wide variation of the corrosion morphology magnesium alloy AZ91D specimens after the surface modification using polylactic acid coating, compared with the unmodified.

Corrosion of Amorphous Fe73.5Si13.5B9Nb3Cu1 Alloys on the Synergistic Effect of Chloride and Hydroxyl Ions

2011 ◽  
Vol 284-286 ◽  
pp. 1550-1553
Author(s):  
Ming Sheng Li ◽  
Dan Zhang ◽  
Yi Ming Jiang ◽  
Jin Li
Keyword(s):  
Magnetic Properties ◽  
Electrochemical Impedance Spectroscopy ◽  
Sodium Chloride ◽  
Impedance Spectroscopy ◽  
Service Life ◽  
Corrosion Rate ◽  
Electrochemical Impedance ◽  
Soft Magnetic Properties ◽  
High Concentration ◽  
Soft Magnetic

The soft-magnetic properties and service life of amorphous or nanocrystalline Fe73.5Si13.5B9Nb3Cu1 have been influenced by the corrosion of the alloy. In this study, the electrochemical corrosions of amorphous Fe73.5Si13.5B9Nb3Cu1 in the blend solutions of sodium chloride and sodium hydroxide were investigated by linear polarization (PLZ) and electrochemical impedance spectroscopy (EIS) technique. The presence of OH- in the blend solution gave rise to typical passivation of the alloy. A suitable concentration of OH- was required for the low corrosion rate. And the higher concentration of OH- led to a faster corrosion. Increase of concentration of Cl- aroused more obvious corrosion. These results were ascribed to the deteriorating effect of Cl- and high-concentration OH- on the passive film formed on the surface of amorphous Fe73.5Si13.5B9Nb3Cu1.

scholarly journals Electrochemical Impedance Spectroscopy for the Measurement of the Corrosion Rate of Magnesium Alloys: Brief Review and Challenges

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 775 ◽  
Author(s):  
Sebastián Feliu
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Electrochemical Impedance ◽  
State Of The Art ◽  
Point Of View ◽  
Reliable Determination ◽  
Corrosion Rates ◽  
Non Destructive

From a technological point of view, measurement of the corrosion rate of magnesium (Mg) and its alloys is critical for lifetime predictions of Mg-based structures and for comparative assessments of their corrosion protection ability. Whilst weight loss, hydrogen evolution, and polarization curves methods are frequently used for measuring the corrosion rate, the determination of values by electrochemical impedance spectroscopy (EIS) is relatively scarce and has only been realized recently. This technique seems to be the most suitable for monitoring corrosion rate values due to its “non-destructive” character, its reproducibility, and its reliable determination of small corrosion rates, much lower than those measured by other techniques. This review aims to picture the state-of-the-art technique of using EIS for measuring the corrosion rate of Mg. This paper starts by introducing some fundamental aspects of the most widely used methods for monitoring the corrosion rate of Mg/Mg alloy and continues by briefly explaining some of the fundamental concepts surrounding EIS, which are essential for the user to be able to understand how to interpret the EIS spectra. Lastly, these concepts are applied, and different approaches that have been proposed to obtain quantitative values of corrosion rate since the 1990s are discussed.

Corrosion Behavior of Hot-Dip Galvanized Reinforcing Steel Using Electrochemical Impedance Spectroscopy

2011 ◽  
Vol 250-253 ◽  
pp. 222-227 ◽  
Author(s):  
Bi Lan Lin ◽  
Yu Ye Xu
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Electrochemical Impedance ◽  
Chloride Ions ◽  
Reinforcing Steel ◽  
Effective Measure ◽  
Passivation Film ◽  
Corrosion Behaviors

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.

scholarly journals Inhibition of Brass Corrosion in Acid Medium Using Thiazoles

2013 ◽  
Vol 14 ◽  
pp. 87-102
Author(s):  
K.K. Taha ◽  
Musa E. Mohamed ◽  
S.A. Khalil ◽  
S.A. Talab
Keyword(s):  
Weight Loss ◽  
Thermal Properties ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Heat Exchangers ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Zinc Dissolution

Brass as an alloy composed mainly of copper is great industrial uses such as heat exchangers and similar other facility due to its good thermal properties. Due to the presence of the considerable ratio of zinc the alloy suffers from zinc dissolution or dezincification. Dezincification rate increases with the increase in the ratio of zinc in the alloy. In this study benzothiazole (BTH) and its substituent’s 2-methylbenzothiazole (MeBTH), 2-aminobenzothiazole (ABTH), 2-mercaptobenzothiazole (MBTH) and 2-phenylbenzothiazole (PhBTH) have been used as corrosion inhibitors for α-brass in stirred 0.1 M HClO4. The methods of investigation include weight loss, Tafel and linear polarizations and electrochemical impedance spectroscopy. The order of inhibition efficiency (%E) was calculated and the values obtained has indicated the sequence of inhibition efficiency was found to be BTH < MeBTH < ABTH < PhBTH < MBTH. The calculated values of thermodynamic parameters support this order. The inhibitors were found to suppress the corrosion rate by the formation of films which were identified by IR, SEM and EDAX techniques.

Corrosion Behavior of Al-Sn-Bi Alloys in Ethylene Glycol-Water Mixtures

CORROSION ◽  
2012 ◽  
Vol 68 (5) ◽  
pp. 421-431
Author(s):  
J.L. Gama-Ferrer ◽  
J.G. Gonzalez-Rodriguez ◽  
I. Rosales ◽  
J. Uruchurtu
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Ethylene Glycol ◽  
Corrosion Behavior ◽  
Potentiodynamic Polarization ◽  
Electrochemical Noise ◽  
Electrochemical Impedance ◽  
Electrochemical Techniques ◽  
Potentiodynamic Polarization Curves

A study of the effect of Sn (1, 2, 3.5, 4.5, and 5 wt%) and Bi (0.5, 1.5, 3, and 4%) on the corrosion behavior of Al in ethylene glycol (C2H6O2)-40% water mixtures at 20, 40, and 60°C has been carried out using electrochemical techniques. Techniques include potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), and electrochemical noise (EN) measurements. The three techniques have shown that additions of either Sn or Bi contents increased the corrosion rate of pure Al in all cases, and that generally speaking, the corrosion rate increased by increasing the temperature except for the alloy containing 1% Sn + 4% Bi, which showed the lowest corrosion rate at 60°C. This was because of a galvanic effect from the presence of Sn and/or Bi particles on the surface alloy, which acted as local cathodes, leading to an acceleration of corrosion. Nyquist diagrams showed two semicircles at 20°C and only one at 40°C or 60°C for all the alloys, showing two different corrosion-controlling mechanisms. EN measurements showed evidence of a mixture of both localized and uniform types of corrosion for all Al-based alloys.

Study of Corrosion Rate of Buried Steel in Soil by Electrochemical Impedance Spectroscopy

2018 ◽  
Vol 85 (13) ◽  
pp. 599-604
Author(s):  
Shingo Mineta ◽  
Shota Ohki ◽  
Mamoru Mizunuma ◽  
Soichi Oka
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Electrochemical Impedance

Effect of the Fe/Cu Relationship Corrosion and low Alloying Elements on Corrosion Behavior of Cast Aluminum Parts

2016 ◽  
Vol 1815 ◽  
Author(s):  
C. Rodríguez-Rivera ◽  
J.A. García-Hinojosa ◽  
F.J. Rodríguez-Gómez
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Aluminum Alloys ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Open Circuit Potential ◽  
Electrochemical Impedance ◽  
Open Circuit ◽  
Localized Corrosion ◽  
Corrosion Mechanism ◽  
Corrosion Morphology

ABSTRACTThe aim of this study is to compare the corrosion rate of aluminum alloys for ornamental pieces. Three Fe/Cu relationships were tested in order to improve hardness and brightness in aluminum pieces since these alloys are used in the making of ornamental pieces. The variation on Fe/Cu content could result in modification on corrosion rate, since a metallographic characterization must be carried out identifying the presence of intermetallic phases. The presence of these elements could result in increasing corrosion rate, or even in modification of corrosion morphology, so localized corrosion could be expected.The assessment of corrosion rate was carried out in saline media, since chlorides are ions that promote localized corrosion. Electrochemical techniques (polarization curves and Tafel plots) were used in order to evaluate the attack in aluminum pieces; electrochemical impedance spectroscopy was also employed with voltage amplitude of 10 mV rms, and a frequency range from 10,000 Hz to 0.01 Hz. A typical three electrodes cell was used, exposing an area of one cm2. Before polarization, open circuit potential was monitored for an hour looking for a steady state. All conditions were tested for triplicate.The behavior of open circuit potential vs. time, and polarization curves was analyzed; a corrosion mechanism is proposed according to the electrochemical control. Polarization rate was calculated by using Tafel plots and, an electrochemical impedance spectroscopy analysis by using equivalent electric circuits is shown. Electrochemical impedance will yield information about corrosion morphology that is backed with microscopic inspection.The objective of this study is to compare the corrosion rate of aluminum alloys for ornamental pieces in order to determine the effect of the relationship Fe/Cu on the corrosion mechanism in aluminum parts for ornamental pieces.

Sign in / Sign up

Export Citation Format

Share Document