Influence of Surface Finishing on Corrosion Behaviour of 3D Printed TiAlV Alloy

Additive manufacturing is currently one of the promising methods for the fabrication of products of complex shapes. It is also used in medical applications, thanks to technological progress, which also enables the printing of metallic materials. However, the final products often have to undergo a final surface treatment. In this work, the influence of surface finishing on the corrosion behavior of the medical alloy Ti-6Al-4V prepared by the selective laser melting technique is studied. The samples were subjected to mechanical, chemical and electrochemical treatments. Corrosion behavior was investigated using DC and AC electrochemical techniques such as potentiodynamic and potentiostatic curves and electrochemical impedance spectroscopy. Furthermore, the influence of surface treatments on the possibility of localized corrosion attack was evaluated. The results showed that the surface treatments have a positive effect on the corrosion resistance and reduce the risk of crevice corrosion.

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Assessment of nickel titanium and beta titanium corrosion resistance behavior in fluoride and chloride environments

The Angle Orthodontist ◽

10.2319/091712-740.1 ◽

2013 ◽

Vol 83 (5) ◽

pp. 864-869 ◽

Cited By ~ 8

Author(s):

Elisa J. Kassab ◽

José Ponciano Gomes

Keyword(s):

Corrosion Resistance ◽

Corrosion Behavior ◽

Electrochemical Impedance ◽

Fluoride Concentration ◽

Nickel Titanium ◽

Localized Corrosion ◽

General Corrosion ◽

Nacl Solution ◽

Galvanic Coupling ◽

Beta Titanium

ABSTRACT Objective: To assess the influence of fluoride concentration on the corrosion behavior of nickel titanium (NiTi) superelastic wire and to compare the corrosion resistance of NiTi with that of beta titanium alloy in physiological solution with and without addition of fluoride. Materials and Methods: NiTi corrosion resistance was investigated through electrochemical impedance spectroscopy and anodic polarization in sodium chloride (NaCl 0.15 M) with and without addition of 0.02 M sodium fluoride (NaF), and the results were compared with those associated with beta titanium. The influence of fluoride concentration on NiTi corrosion behavior was assessed in NaCl (0.15 M) with and without 0.02, 0.04, 0.05, 0.07, and 0.12 M NaF solution. Galvanic corrosion between NiTi and beta titanium were investigated. All samples were characterized by scanning electron microscopy. Results: Polarization resistance decreased when NaF concentration was increased, and, depending on NaF concentration, NiTi can suffer localized or generalized corrosion. In NaCl solution with 0.02 M NaF, NiTi suffer localized corrosion, while beta titanium alloys remained passive. Current values near zero were observed by galvanic coupling of NiTi and beta titanium. Conclusions: There is a decrease in NiTi corrosion resistance in the presence of fluoride. The corrosion behavior of NiTi alloy depends on fluoride concentration. When 0.02 and 0.04 M of NaF were added to the NaCl solution, NiTi presented localized corrosion. When NaF concentration increased to 0.05, 0.07, and 0.12 M, the alloy presented general corrosion. NiTi corrosion resistance behavior is lower than that of beta titanium. Galvanic coupling of these alloys does not increase corrosion rates.

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INFLUENCE OF A PREFABRICATED-CROWN ROLLING PROCESS ON THE CORROSION BEHAVIOUR OF AZ31 MAGNESIUM ALLOY

Materiali in tehnologije ◽

10.17222/mit.2020.219 ◽

2021 ◽

Vol 55 (4) ◽

Author(s):

Zhiquan Huang ◽

Jinchao Zou ◽

Junpeng Wang ◽

Yanjie Pei ◽

Renyao Huang ◽

...

Keyword(s):

Magnesium Alloy ◽

Corrosion Behavior ◽

Electrochemical Impedance ◽

Corrosion Behaviour ◽

Plate Thickness ◽

Az31 Alloy ◽

Rolling Process ◽

Charge Transfer Resistance ◽

Az31 Magnesium Alloy ◽

Transfer Resistance

The present study aims to investigate the effect of a prefabricated-crown rolling process on the corrosion characteristic of the AZ31 magnesium alloy. Specimens made of the AZ31 alloy were rolled under various crown conditions, and their microstructure evolution and corrosion behavior were analyzed. The corrosion behavior was studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed that the corrosion-current density of the AZ31 alloy with a side pressure of 37.5 % of the plate thickness of the precast convexity decreased from 3.79 × 10–6 A/cm2 to 1.80 × 10–6 A/cm2, and the difference between the edge and the middle of the AZ31 alloy was shortened from 2.05 × 10–6 A/cm2 to 1.14 × 10–6 A/cm2. The charge-transfer resistance also increased from 507.1 Ω·cm2 to 581.2 Ω·cm2. The improvement in the corrosion resistance is a result of the more stable corrosion products and microstructure refinement formed after the prefabricated-crown rolling process.

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Corrosion of Mechanically Alloyed Nanostructured FeAl Intermetallic Powders

Advances in Materials Science and Engineering ◽

10.1155/2012/629802 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

A. Torres-Islas ◽

C. Carachure ◽

S. Serna ◽

B. Campillo ◽

G. Rosas

Keyword(s):

Corrosion Behavior ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Corrosion Current ◽

Test Time ◽

Uniform Corrosion ◽

Mechanically Alloyed ◽

Solution Ph ◽

Surface Corrosion ◽

Electrochemical Testing

The corrosion behavior of the Fe40Al60nanostructured intermetallic composition was studied using electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) techniques with an innovative electrochemical cell arrangement. The Fe40Al60(% at) intermetallic composition was obtained by mechanical alloying using elemental powders of Fe (99.99%) and Al (99.99%). All electrochemical testing was carried out in Fe40Al60particles that were in water with different pH values. Temperature and test time were also varied. The experimental data was analyzed as an indicator of the monitoring of the particle corrosion current densityicorr. Different oxide types that were formed at surface particle were found. These oxides promote two types of surface corrosion mechanisms: (i) diffusion and (ii) charge transfer mechanisms, which are a function oficorrbehavior of the solution, pH, temperature, and test time. The intermetallic was characterized before and after each test by transmission electron microscopy. Furthermore, the results show that at the surface particles uniform corrosion takes place. These results confirm that it is possible to sense the nanoparticle corrosion behavior by EIS and LPR conventional electrochemical techniques.

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Corrosion Behavior of Al in Ethanol–Gasoline Blends

Energies ◽

10.3390/en13215544 ◽

2020 ◽

Vol 13 (21) ◽

pp. 5544

Author(s):

Alfredo Brito-Franco ◽

Jorge Uruchurtu ◽

Isai Rosales-Cadena ◽

Roy Lopez-Sesenes ◽

Sergio Alonso Serna-Barquera ◽

...

Keyword(s):

Corrosion Behavior ◽

Sugar Cane ◽

Electrochemical Noise ◽

Electrochemical Impedance ◽

Pure Aluminum ◽

Electrochemical Techniques ◽

Intermediate Compound ◽

Corrosion Process ◽

Corrosion Rates ◽

Adsorption Desorption

The corrosion behavior of pure aluminum (Al) in 20 v/v% ethanol–gasoline blends has been studied using electrochemical techniques. Ethanol was obtained from different fruits including sugar cane, oranges, apples, or mangos, whereas other techniques included lineal polarization resistance, electrochemical noise, and electrochemical impedance spectroscopy for 90 days. Results have shown that corrosion rates for Al in all the blends were higher than that obtained in gasoline. In addition, the highest corrosion rate was obtained in the blend containing ethanol obtained from sugar cane. The corrosion process was under charge transfer control in all blends; however, for some exposure times, it was under the adsorption/desorption control of an intermediate compound. Al was susceptible to a localized, plotting type of corrosion in all blends, but they were bigger in size and in number in the blend containing ethanol obtained from sugar cane.

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Influence of phytic acid on the corrosion behavior of carbon steel with different surface treatments

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-05-2018-1937 ◽

2018 ◽

Vol 65 (6) ◽

pp. 658-667 ◽

Cited By ~ 1

Author(s):

Yingjun Zhang ◽

Baojie Dou ◽

Yawei Shao ◽

Xue-Jun Cui ◽

Yanqiu Wang ◽

...

Keyword(s):

Carbon Steel ◽

Corrosion Inhibitor ◽

Corrosion Inhibition ◽

Corrosion Behavior ◽

Electrochemical Impedance ◽

Surface Condition ◽

Energy Dispersive Spectrometer ◽

Surface Treatments ◽

Inhibition Mechanism ◽

Content Type

Purpose This paper aim to investigate the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments, and interpret the inhibition mechanism of PA on the steel with different surface treatments. Design/methodology/approach The influence of PA on the corrosion behavior of blast cleaned or rusty steel was investigated by means of electrochemical impedance spectroscopy (EIS). The EIS data were analyzed using the @ZsimpWin commercial software. The morphology and component of steel after immersion were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), Fourier transformation infrared (FTIR) and X-ray diffractometer (XRD). Findings EIS analysis results indicated that PA had good corrosion inhibition for blast cleaned or rusty steel. SEM, EDS, FTIR and XRD further indicated that PA had two main corrosion inhibition processes for the corrosion inhibition of blast cleaned or rusty steel: corrosion dissolution and formation of protective barrier layers. Originality/value Most published works focus the attention only toward the effect of corrosion inhibitor for the clean metal surfaces. However, the surface condition of metal sometimes is unsatisfactory in the practical application of corrosion inhibitor, such as existing residual rust. Some studies also have shown that several corrosion inhibitors could be applied on partially rusted substrates. These inhibitors mainly include tannins and phosphoric acid, but not PA. Therefore, the authors investigated the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments in this paper.

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EIS Study of Corrosion Behavior of Hot-Dip Galvanized Steel in 5% NaCl Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.779 ◽

2011 ◽

Vol 335-336 ◽

pp. 779-782

Author(s):

Shi Quan He ◽

Hui Zhong

Keyword(s):

Aqueous Solution ◽

Equivalent Circuit ◽

Corrosion Behavior ◽

Immersion Time ◽

Electrochemical Impedance ◽

Corrosion Behaviour ◽

Impedance Spectrum ◽

Corrosion Products ◽

Galvanized Steel ◽

Electrochemical Impedance Spectrum

Corrosion behaviour of hot-dip galvanized steel in 5% NaCl aqueous solution was studied by electrochemical impedance spectrum (EIS) technique. The results revealed that corrosion behaviour of hot-dip galvanized steel has a great relationship with immersion time. With the increase of immersion time, corrosion products are constantly changing, and the impedance of corrosion products are different. Parameters fitted by equivalent circuit show that the impedance of corrosion products increased at first, then decreased.

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

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.835.131 ◽

2016 ◽

Vol 835 ◽

pp. 131-135 ◽

Cited By ~ 2

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.

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Electrochemical Investigation of the Effects of Acid Concentration and Dissolved Oxygen on the Corrosion Behavior of Austenitic Low-Nickel Stainless Steels in Citric Acid

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.835.115 ◽

2016 ◽

Vol 835 ◽

pp. 115-120

Author(s):

Francis Mulimbayan ◽

Manolo G. Mena

Keyword(s):

Corrosion Resistance ◽

Citric Acid ◽

Dissolved Oxygen ◽

Corrosion Behavior ◽

Polarization Resistance ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Open Circuit ◽

Human Consumption ◽

Face Centered Cubic

All materials which are intended to have in contact with food and other commodities produced or processed for human consumption are called food contact materials (FCM’s). Stainless steel (SS) – a widely known metallic FCM is used mainly in processing equipment, containers and household utensils. It is known for having numerous industrial and domestic applications worldwide due to its special characteristics of having notable corrosion resistance. However, this corrosion resistance is not all-encompassing since SS may still undergo degradation when subjected to a specific corrosion-inducing environment. SS may be classified according to its microstructure. If the atoms which make up the SS can be viewed as having a face-centered cubic structure, then the alloy is said to be austenitic. This SS grades include the conventional 300-series and the newly-developed 200-series. The former has superior corrosion resistance while the latter is far cheaper. In this study, the corrosion behavior of AISI 202 SS in two different levels of dissolved oxygen (O2) and three acid concentrations was investigated using electrochemical techniques, namely, open-circuit potential (OCP) measurements and electrochemical impedance spectroscopy (EIS). As the concentration of citric acid is increased, the measured OCP values of the alloy decreased and the polarization resistance (Rp) decreased, indicating decrease in alloy stability and decline in the corrosion resistance, respectively. With regards to effects of dissolved O2, results revealed that increasing the level of dissolved O2 has consequently increased the polarization resistance and shifted the OCP to more positive values. All the generated Nyquist plots exhibited a depressed capacitive loops indicating that corrosion in the designated solution occurred with charge transfer as the rate-determining step.

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Characterisation of Reinforced BTSE Films Deposited on Anodized Aluminium Substrate

Revista de Chimie ◽

10.37358/rc.18.11.6663 ◽

2018 ◽

Vol 69 (11) ◽

pp. 2964-2968

Author(s):

Ioana Alina Ciobotaru ◽

Oana Claudia Ciobotea Barbu ◽

Florin Mihai Benga ◽

Danut Ionel Vaireanu

Keyword(s):

Electrochemical Impedance ◽

Corrosion Behaviour ◽

Substrate Surface ◽

Electrochemical Techniques ◽

Surface Characteristics ◽

Open Circuit ◽

Point Of View ◽

Aluminium Substrate ◽

Anodised Aluminium ◽

Deposited Films

This paper discusses the improvements achieved in the anticorrosive properties of some silane films by pretreating the metallic substrate prior to films deposition and by reinforcement with some reinforcement agents. One has compared the behaviour of silane films, deposited on aluminium substrate, and the reinforced silane films deposited on anodised aluminium substrate. The use of scanning electron microscopy highlighted the modifications of substrate surface characteristics prior and after the anodisation process, while electrochemical techniques such as open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization were employed in order to characterize the deposited films from the corrosion behaviour point of view.

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Study of Corrosion Damage Under Protective Coatings

10.1115/imece2001/nde-25818 ◽

2001 ◽

Author(s):

Mohammad Khobaib ◽

Jochen Hoffmann ◽

Shamachary Sathish ◽

Michael S. Donley

Keyword(s):

Spatial Resolution ◽

Electrochemical Impedance ◽

Protective Coatings ◽

Salt Spray ◽

Electrochemical Techniques ◽

Corrosion Damage ◽

Acoustic Microscopy ◽

Localized Corrosion ◽

Corrosion Activity ◽

Military Aircraft

Abstract Polymer coatings provide an excellent corrosion barrier for Al-skinned military aircraft. However, the degradation and damage of the coatings in their service life over time leads to the initiation of corrosion damage at the substrate level. Early detection and negation of such activity can provide extensive cost savings. Several Electrochemical techniques and Non Destructive Evaluation (NDE) show promise in detecting the onset of corrosion under such coatings. Current accelerated testing of aircraft coating systems for corrosion protection relies heavily on salt spray methods. Electrochemical techniques such as Electrochemical Impedance Spectroscopy (EIS) and Electrochemical Noise Methods (ENM) provide insight into the global properties of a coating system, and both techniques are being used on a limited basis. However, there is a need to investigate corrosion events with greater spatial resolution under coatings at the metal/coating interface. Such corrosion activity may be related to coating defects and variations in the surface chemistry of the underlying metal. The Scanning Vibrating Electrode Technique (SVET) has been developed to allow the investigation of localized corrosion activity with high spatial resolution. Such activity may be associated with coating defects or galvanic coupled regions of the metal surface. Electrochemical and NDE techniques were used to investigate the early stage of corrosion activity under protective coatings. Coatings in this investigation ranged from a simple epoxy amine to commercially used military aircraft polyurethane coatings. SVET testing of panels with intact high-resistance barrier coatings could not reveal corrosion damage under normal testing conditions because of little or no corrosion activity within the limited exposure time. Chemical, mechanical, and electrochemical means of accelerating the corrosion damage were utilized to obtain results in a reasonable time frame. Corrosion initiation and its progress under the coating were studied in detail and the results are discussed here. Complimentary high-resolution NDE techniques, such as Scanning Acoustic Microscopy (SAM) and Fan Thermography measurements were used to identify the corrosion sites. The overall objective of this investigation is to establish a correlation between the electrochemical and NDE techniques.

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