scholarly journals Quantifying an acceptable open-circuit corrosion current for aluminum–air batteries

2021 ◽  
Vol 2 (5) ◽  
pp. 1595-1599
Author(s):  
Brandon J. Hopkins ◽  
Debra R. Rolison
Keyword(s):  
Corrosion Current ◽  
Open Circuit ◽  
Corrosion Model ◽  
Commercial Applications

By deriving a corrosion model, we show that anodes in most aluminum–air batteries corrode too quickly for commercial applications.

Corrosion Behaviour of In Situ AlxNiy Reinforced AA6061 Composite

2021 ◽  
Vol 882 ◽  
pp. 96-103
Author(s):  
A.D. Vishwanatha ◽  
D.M. Shivanna ◽  
Bijayani Panda
Keyword(s):  
Corrosion Potential ◽  
Corrosion Behaviour ◽  
Corrosion Current ◽  
Open Circuit ◽  
Homogeneous Distribution ◽  
Initial Increase ◽  
Weight Percentage ◽  
Aa6061 Alloy ◽  
Ni Addition

In-situ AlxNiy reinforced aluminium matrix composites (AMCs) were produced by stir-casting route by adding 5, 10 and 15 weight percentage (wt.%) of Ni to AA6061 aluminum alloy. The density, porosity, microstructure, hardness and corrosion behaviour of the as-cast AMCs was studied and compared with that of the as-cast AA6061 alloy. The porosity in all the castings was found to be less than 0.1%. Further, the porosity was found to decrease with increase in Ni addition. Optical microscopy studies showed that in-situ formed AlxNiy was distributed along the dendritic arms. The distribution became non-homogeneous and coarse with increase in AlxNiy content. The coarse distribution of AlxNiy in the AA6061 matrix also resulted in the decrease in hardness of the composite, after an initial increase in hardness till 10 wt.% Ni addition. The open circuit potential (OCP) and corrosion potential (Ecorr) of the AMCs with 5, 10 and 15 wt. of % Ni addition was noble than that of the AA6061 alloy. This was understood to be due to the presence of AlxNiy intermetallic which is known to have a noble corrosion potential than the aluminium alloy. However, the corrosion current (icorr) increased while the polarization resistance (Rp) decreased with increase in Ni addition in the AMC. This indicates that the coarse non-homogeneous distribution of in-situ AlxNiy had a detrimental effect on the corrosion performance of the AMCs.

scholarly journals From Waste to Valuable Resource: Lignin as a Sustainable Anti-Corrosion Coating

Coatings ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 454 ◽  
Author(s):  
Arman Dastpak ◽  
Kirsi Yliniemi ◽  
Mariana de Oliveira Monteiro ◽  
Sarah Höhn ◽  
Sannakaisa Virtanen ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Open Circuit Potential ◽  
Electrochemical Impedance ◽  
Steel Corrosion ◽  
Linear Sweep Voltammetry ◽  
Corrosion Current ◽  
Polymer Coatings ◽  
Open Circuit ◽  
Linear Sweep ◽  
Cyclic Potentiodynamic Polarization

In this study, a waste of biorefinery—lignin—is investigated as an anticorrosion coating on stainless steel. Corrosion behavior of two lignin types (hardwood beech and softwood spruce) was studied by electrochemical measurements (linear sweep voltammetry, open circuit potential, potentiostatic polarization, cyclic potentiodynamic polarization, and electrochemical impedance measurements) during exposure to simulated body fluid (SBF) or phosphate buffer (PBS). Results from linear sweep voltammetry of lignin-coated samples, in particular, demonstrated a reduction in corrosion current density between 1 and 3 orders of magnitude cf. blank stainless steel. Furthermore, results from cross cut adhesion tests on lignin-coated samples demonstrated that the best possible adhesion (grade 0) of ISO 2409 standard was achieved for the investigated novel coatings. Such findings suggest that lignin materials could transform the field of organic coatings towards more sustainable alternatives by replacing non-renewable polymer coatings.

scholarly journals Corrosion investigations of Al-Si casting alloys in 0.6 M NaCl solution

2021 ◽  
Vol 41 (3) ◽  
Author(s):  
Sunčana Smokvina Hanza ◽  
Ladislav Vrsalović ◽  
Lovro Štic ◽  
Lovro Liverić
Keyword(s):  
Potentiodynamic Polarization ◽  
Electrochemical Behavior ◽  
Die Casting ◽  
Electrochemical Corrosion ◽  
Microstructural Characterization ◽  
Casting Process ◽  
Corrosion Current ◽  
Optical Microscope ◽  
Open Circuit ◽  
Polarization Measurements

This paper presents results of the corrosion investigations of specimens made from finished parts for the automotive industry, produced by high-pressure die casting and gravity die casting process of six Al-Si alloys (40000 series). Open circuit potential and potentiodynamic polarization measurements have been performed using a potentiostat with three-electrode set-up in 0.6 M NaCl naturally aerated solution. Microstructural characterization before and after electrochemical investigations has been carried out with optical microscope to establish the connection between microstructure and corrosion parameters of investigated alloys and to analyze and record surface changes of each sample due to electrochemical corrosion. All alloys show good corrosion resistance, which manifests with low values of corrosion rates, calculated from the corrosion current densities obtained from potentiodynamic polarization measurements. Differences in electrochemical behavior appear due to the distinctions in their chemical composition and microstructure. The type of casting process does not affect electrochemical behavior of Al-Si alloys.

scholarly journals Corrosion behaviour of an AlZnSnSrGa alloy in aqueous solutions of NaCl and Na2So4

2000 ◽  
Vol 65 (1) ◽  
pp. 73-81
Author(s):  
P. Zivkovic ◽  
J. Pjescic ◽  
S. Mentus
Keyword(s):  
Corrosion Rate ◽  
Aqueous Solutions ◽  
Polarization Resistance ◽  
Corrosion Current Density ◽  
Corrosion Behaviour ◽  
Base Material ◽  
Corrosion Current ◽  
Open Circuit ◽  
Base Metals ◽  
Aluminium Plant

The alloy composed of Al(95.53%), Zn(2.85%), Sn(0.515%), Ga(0.1%) and Sr(0.009%), with the weight percents in the parentheses, was prepared by melting, using Al(99.84%), a product of the Aluminium Plant-Podgorica, as the base material. The corrosion behaviour of this alloy was tested in relation to the behaviour of the base metals, by both open curcuit potential and polarization resistance methods, in aqueous solutions of both NaCl and Na2SO4, the concentration of which varied within the range 0.00051 - 0.51 mol dm -3. Over the whole salt concentration ranges, the corrosion parameters indicate that the corrosion rate of the alloy is significantly higher than the rate of the base material. For instance, for the concentration range 0.00051 - 0.51 mol dm -3 , the stationary open circuit potentials, related to SCE, in NaCl solutions were - 1.200 to - 1.460 V for the alloy and - 0.693 to - 0.920 V for Al, while in Na2SO4 solutions, the stationary open circuit potentials were - 1.190 to - 1.465V for the alloy and - 0.780 to - 0.860V for Al. At the same time, the corrosion current density in NaCl solutions varied within 11-89 mA cm -2 for the alloy and 0.35 - 0.80 for Al, while in Na2SO4 solutions it amounted to 5.7.52 mA cm -2 for the alloy and 0.28 - 0.88 mA cm -2 for Al.

Electrochemical Corrosion Behaviour of ZrN Film in Various Corrosive Fluid

2015 ◽  
Vol 3 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Vishnu R. ◽  
Jiten Das ◽  
S. B. Arya ◽  
Manish Roy
Keyword(s):  
Sea Water ◽  
Corrosion Behaviour ◽  
Water Solution ◽  
Electrochemical Corrosion ◽  
High Hardness ◽  
Corrosion Current ◽  
Plain Carbon Steel ◽  
Open Circuit ◽  
Protective Film ◽  
Hank’S Solution

Recently, ZrN has been attracting interest for its excellent corrosion resistance, biocompatibility, high hardness, good lubricity and ductility. Although tribological study of ZrN coating has been carried out extensively, investigation related to corrosion of ZrN film is limited. In view of this and in view of possible applications of ZrN film in several engineering components, the present investigation has been undertaken to evaluate the corrosion response of ZrN film in seawater solution, Hank's solution, 0.5M H2SO4solution and 0.5M HCl solutions. Towards that purpose, potentiostatic, open circuit potential and potentiodynamic study of ZrN film deposited on plain carbon steel has been carried out in all these solutions. Results indicate that stable protective film is formed on the surface of ZrN coating in all these solution except 0.5M H2SO4 solution. The formation of protective film on ZrN coating is fastest in sea water solution and it is slowest in the Cl¯ ions containing media, 0.5 M HCl. The corrosion current is highest for 0.5M H2SO4 acid solution and least for Hank's solution.

scholarly journals Mechanical and Corrosion Properties of Mg-Based Alloys with Gd Addition

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1775 ◽  
Author(s):  
Aneta Kania ◽  
Ryszard Nowosielski ◽  
Agnieszka Gawlas-Mucha ◽  
Rafał Babilas
Keyword(s):  
Open Circuit Potential ◽  
Corrosion Potential ◽  
Orthopedic Implants ◽  
Corrosion Current ◽  
Medical Application ◽  
Open Circuit ◽  
Dendritic Microstructure ◽  
Corrosion Properties ◽  
Electrochemical Parameters ◽  
Mechanical And Corrosion Properties

Magnesium alloys with rare earth metals are very attractive materials for medical application because of satisfactory mechanical properties. Nevertheless, low corrosion resistance is an obstacle in the use of Mg alloys as resorbable orthopedic implants. The paper presents results of mechanical and corrosion properties of MgCa5-xZn1Gdx (x = 1, 2, and 3 wt. %) alloys. Based on the microscopic observations it was stated that the studied alloys show a dendritic microstructure with interdendritic solute rich regions. The phase analysis reveals an occurrence of α-Mg and Mg2Ca, Ca2Mg6Zn3 phases that are thermodynamic predictions, and stated Mg26Zn59Gd7 phases in MgCa5-xZn1Gdx (x = 1, 2, and 3 wt. %) alloys. The Mg26Zn59Gd7 phases are visible as lamellar precipitations along interdendritic regions. It was confirmed that an increase of Gd content from 1 to 3 wt. % improves ultimate tensile (Rm; from 74 to 89 MPa) and compressive strength (Rc; from 184 to 221 MPa). Moreover, the studied alloys are active in Ringer’s solution. They are characterized by an increase of corrosion potential (Ecorr) of about 150 mV in comparison with values of open circuit potential (EOCP). The best electrochemical parameters (e.g., corrosion current density, icorr, polarization resistance, Rp, and Ecorr) were obtained for the MgCa3Zn1Gd2 alloy.

Biodegradable Mg for Bone Implants: Corrosion and Osteoblast Culture Studies

2008 ◽  
Author(s):  
YeoHeung Yun ◽  
Zhongyun Dong ◽  
Dianer Yang ◽  
Vesselin Shanov ◽  
Zhigang Xu ◽  
...  
Keyword(s):  
Cell Culture ◽  
Electrochemical Impedance ◽  
Culture Media ◽  
Corrosion Current ◽  
Visual Observation ◽  
Open Circuit ◽  
Biodegradable Implant ◽  
Cell Culture Media ◽  
X Ray ◽  
Implant Material

Corrosion and cell culture experiments were performed to evaluate magnesium (Mg) as a possible biodegradable implant material. The corrosion current and potential of a Mg disk were measured in different physiological solutions. The corrosion currents in cell culture media were found to be higher than in deionized water, which verifies that corrosion of Mg occurs faster in chloride solution. Weight loss, open-circuit potential, and electrochemical impedance spectroscopy measurements were also performed. The Mg specimens were also characterized using an environmental scanning electron microscope and energy-dispersive x-ray analysis (EDAX). The x-ray analysis showed that in the cell culture media a passive interfacial layer containing oxygen, chloride, phosphate, and potassium formed on the samples. U2OS cells were then co-cultured with a Mg specimen for up to one week. Based on visual observation, cell growth and function were not significantly altered by the presence of the corroding Mg sample. These initial results indicate that Mg may be suitable as a biodegradable implant material. Future work will develop small sensors to investigate interfacial biocompatibility of Mg implants.

scholarly journals Polyaniline/Palm Oil Blend for Anticorrosion of Mild Steel in Saline Environment

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Mohd Rashid ◽  
Suhail Sabir ◽  
Afidah A. Rahim ◽  
Umesh Waware
Keyword(s):  
Mild Steel ◽  
Palm Oil ◽  
Potentiodynamic Polarization ◽  
Protective Layer ◽  
Corrosion Current ◽  
Charge Transfer Resistance ◽  
Open Circuit ◽  
Oxidation Potential ◽  
Physical Interaction ◽  
Transfer Resistance

The corrosion protective performance of polyaniline/palm oil (PAni-PO) blend coated on mild steel in 3% NaCl aqueous solutions has been evaluated by electrochemical methods, namely, open circuit potential (ocp), potentiodynamic polarization, and EIS spectroscopy. The surface of mild steel was covered by a dark green protective layer due to the physical interaction between the coating and steel. The permanent shifts of ocp and potentiodynamic polarization towards higher positive value of oxidation potential by about 800 mV and by a decrease in corrosion current density by sixfold in magnitude and an increase of 10 orders of magnitude in charge transfer resistance are due to protective coating.

Comparative Study of the Corrosion Behavior of Low-Nickel AISI 202 and Conventional AISI 304 Stainless Steels in Citric Acid Using Electrochemical Techniques

2016 ◽  
Vol 835 ◽  
pp. 131-135 ◽  
Author(s):  
Francis Mulimbayan ◽  
Manolo G. Mena
Keyword(s):  
Stainless Steel ◽  
Citric Acid ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Electrochemical Techniques ◽  
Corrosion Current ◽  
Open Circuit ◽  
Corrosion Mechanism ◽  
Protective Film ◽  
Aisi 304

Stainless steel (SS) is one of the most commonly used metallic food contact materials. It may be classified based on its microstructure whether ferritic, austenitic, martensitic, duplex or precipitation hardened. Austenitic SS, among mentioned grades, has the largest contribution to market due to its numerous industrial and domestic applications. In this study, the corrosion behavior of AISI 202 SS – a cheaper grade of stainless steel, in three different solution temperatures of citric acid was investigated using different electrochemical techniques such as open-circuit potential (OCP) measurements, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results were compared to that obtained from conventional AISI 304 SS. OCP, polarization and impedance measurements agreed that AISI 202 SS has comparable resistance to that of AISI 304 SS in citric acid at ambient temperature and at 50 °C. At 70 °C, results of OCP measurements suggest that AISI 304 SS exhibited greater performance as indicated by more positive OCP values in the designated solution. EIS results indicate that the two alloys have identical corrosion resistance even at 70 °C as indicated by their comparable polarization resistance (Rp). The corrosion mechanism in both alloys is charge-transfer controlled as indicated by depressed semi-circular appearance of the generated Nyquist plots. The values of corrosion current densities (icorr) extracted from polarization curves indicate that the initial corrosion rates were higher in AISI 304 than AISI 202 SS suggesting that formation of more protective film may have occurred on the former alloy.

Some Limitations of the Linear Polarization Techniques in Evaluating Corrosion Behavior

CORROSION ◽  
1969 ◽  
Vol 25 (11) ◽  
pp. 455-461 ◽  
Author(s):  
M. E. INDIG ◽  
C. GROOT
Keyword(s):  
Corrosion Behavior ◽  
Linear Polarization ◽  
Saturation Pressure ◽  
Reference Electrode ◽  
Corrosion Current ◽  
Open Circuit ◽  
Platinum Black ◽  
Oxidation Reactions ◽  
Current Time ◽  
Weight Losses

Abstract Current, potential, and weight losses were measured on a system consisting of a stainless steel working electrode, a platinum black reference electrode and platinum auxiliary electrode. The electrolyte was slightly alkaline lithiated water containing 3 ppm hydrogen at 288 C (550 F) and at saturation pressure. Linear polarization measurements were made in the region 0–20 millivolts from the open circuit potential. A corrosion current was calculated from these measurements, using previously cited Tafel constants. The cathodic Tafel constant was also measured directly. The cathodic Tafel slope agreed well with previous values. The corrosion current, estimated by linear extrapolation of the log current vs. voltage curve to zero applied current, agreed well with the current calculated from linear polarization. However, the descaled weight loss of the corroded electrode was only tenth of that computed from the current, time and Faraday's Law. The deviation from the expected corrosion behavior is explained by another anodic half reaction. The steady state exchange current is an equilibrium between several oxidation reactions and several reduction reactions. Only when the corrosion potential is sufficiently removed from the equilibrium potentials of the anodic and cathodic half reactions that constitute the corrosion reaction can the other competing reactions be ignored.

Sign in / Sign up

Export Citation Format

Share Document