Preparation and corrosion resistance of titanium-zirconium/nickel-coated carbon nanotubes chemical nano-composite conversion coatings

2019 ◽  
Vol 66 (3) ◽  
pp. 343-351 ◽  
Author(s):  
Xiaobo Wang ◽  
Zhipeng Li ◽  
Wen Zhan ◽  
Jesong Tu ◽  
Xiaohua Zuo ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Special Functions ◽  
Chemical Conversion ◽  
Conversion Coatings ◽  
Nano Composite ◽  
Content Type ◽  
Titanium Zirconium ◽  
Coated Carbon

Purpose This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to carry out nano-composite technology of nickel-coated carbon nanotubes (Ni-CNTs)-based titanium-zirconium chemical conversion on aluminum alloy substrate. Design/methodology/approach Corrosion behavior of various coatings was investigated using dropping corrosion test, linear polarization and electrochemical impedance spectroscopy. The results showed that the corrosion resistance of the nano-composite conversion coatings was significantly improved to compare with the conventional titanium-zirconium conversion coating. The morphology and microdomain characteristics of the nano-composite conversion coatings were characterized by SEM/eds/EPMA, which indicated that the CNT or Ni-CNTs addition promoting the integrity coverage of coatings in a short time. Findings Surface morphology of titanium-zirconium (Ti-Zr)/Ni-CNT specimens exhibited smooth, compact and little pores. The nano-composite conversion coatings are mainly composed of Al, O, C and Ti elements and contain a small amount of F and Zr elements, which illuminated that CNT or Ni-CNT addition could co-deposit with aluminum and titanium metal oxides. Originality/value The study of corrosion resistance of nano-composite conversion coatings and the micro-zone film-formation characteristics would be provided theoretical support for the development of basic research on surface treatment of aluminum alloys.

Corrosion resistance and characterization studies of calcium series chemical conversion film via green pretreatment on magnesium alloy

2016 ◽  
Vol 63 (6) ◽  
pp. 508-512
Author(s):  
Fengjing Wu ◽  
Xiaojuan Liu ◽  
Xin Xiao
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Electrochemical Impedance ◽  
Chemical Conversion ◽  
Corrosion Current ◽  
Organic Coating ◽  
Hazardous Substances ◽  
Surface Pretreatment ◽  
Content Type ◽  
Az80 Magnesium Alloy

Purpose Magnesium alloys, although valuable, are reactive and require protection before its application in many fields. The purpose of this study was to evaluate a novel anticorrosive chemical conversion film on AZ80 magnesium alloy by environmental-friendly calcium series surface pretreatment. Design/methodology/approach The corrosion resistance of the film was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy in 3.5 Wt.% NaCl solution. The surface morphologies, microstructure and composition of the film were investigated by scanning electron microscopy and energy-dispersive spectroscopy. Findings The corrosion current density of the calcium series film decreased by more than one order of magnitude as compared to that of the AZ80 magnesium alloy. The conversion film presented dry-mud morphology, and its thickness was estimated to be approximately 4 μm. The conversion film was highly hydrophilic, and the organic coating adhesion on treated AZ80 surface was approximately 13.5 MPa. Originality/value Excellent performance of the calcium-based chemical conversion film on Mg alloy was obtained, which does not contain heavy metals or fluorides and completely conforms to European RoHS (Restriction of Hazardous Substances) standard.

Evaluation of the corrosion behavior of AZ31 magnesium alloy with different protein concentrations

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yucong Ma ◽  
Mohd Talha ◽  
Qi Wang ◽  
Zhonghui Li ◽  
Yuanhua Lin
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Surface Film ◽  
Energy Dispersive Spectrometer ◽  
Inhibitory Effect ◽  
Corrosion Process ◽  
High Concentration ◽  
Content Type ◽  
Atomic Force

Purpose The purpose of this paper is to study systematically the corrosion behavior of AZ31 magnesium (Mg) alloy with different concentrations of bovine serum albumin (BSA) (0, 0.5, 1.0, 1.5, 2.0 and 5.0 g/L). Design/methodology/approach Electrochemical impedance spectroscopy and potential dynamic polarization tests were performed to obtain corrosion parameters. Scanning electrochemical microscopy (SECM) was used to analyze the local electrochemical activity of the surface film. Atomic force microscope (AFM), Scanning electron microscope-Energy dispersive spectrometer and Fourier transform infrared spectroscopy were used to determine the surface morphology and chemical composition of the surface film. Findings Experimental results showed the presence of BSA in a certain concentration range (0 to 2.0 g/L) has a greater inhibitory effect on the corrosion of AZ31, however, the presence of high-concentration BSA (5.0 g/L) would sharply reduce the corrosion resistance. Originality/value When the concentration of BSA is less than 2.0 g/L, the corrosion resistance of AZ31 enhances with the concentration. The adsorption BSA layer will come into being a physical barrier to inhibit the corrosion process. However, high-concentration BSA (5.0 g/L) will chelate with dissolved metal ions (such as Mg and Ni) to form soluble complexes, which increases the roughness of the surface and accelerates the corrosion process.

Corrosion resistance of composite coating used for fastener protection

2019 ◽  
Vol 66 (5) ◽  
pp. 595-602
Author(s):  
Zhifeng Lin ◽  
Likun Xu ◽  
Xiangbo Li ◽  
Li Wang ◽  
Weimin Guo ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Carbon Steel ◽  
Composite Coating ◽  
Marine Environment ◽  
Electrochemical Impedance ◽  
Salt Spray ◽  
Diffusion Method ◽  
Economic Losses ◽  
Neutral Salt ◽  
Content Type

Purpose The purpose of this paper is to examine the performance of a fastener composite coating system, sherardized (SD) coating/zinc-aluminum (ZA) coating whether it has good performance in marine environment. Design/methodology/approach In this paper, SD coating was fabricated on fastener surface by solid-diffusion method. ZA coating was fabricated by thermal sintering method. Corrosion behaviours of the composite coating were investigated with potentiodynamic polarization curves, open circuit potential and electrochemical impedance spectroscopy methods. Findings Neutral salt spray (NSS) and deep sea exposure tests revealed that the composite coating had excellent corrosion resistance. Polarization curve tests showed that corrosion current density of the sample with composite coating was significantly decreased, indicating an effective corrosion protection of the composite coating. OCP measurement of the sample in NaCl solution demonstrated that the composite coating had the best cathodic protection effect. The good corrosion resistance of the composite coating was obtained by the synergy of SD and ZA coating. Practical implications SD/ZA coating can be used in marine environment to prolong the life of carbon steel fastener. Social implications SD/ZA composite coating can reduce the risk and accident caused by failed fastener, avoid huge economic losses. Originality/value A new kind of composite coating was explored to protect the carbon steel fastener in marine environment. And the composite coating has the long-term anti-corrosion performance both in simulated and marine environment test.

Role of phytic acid in the corrosion protection of epoxy-coated rusty steel

2019 ◽  
Vol 66 (2) ◽  
pp. 188-194
Author(s):  
Yingjun Zhang ◽  
Xue-Jun Cui ◽  
Yawei Shao ◽  
Yanqiu Wang ◽  
Guozhe Meng ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Phytic Acid ◽  
Corrosion Protection ◽  
Electrochemical Impedance ◽  
Complex Compounds ◽  
Epoxy Coating ◽  
Stable Complex ◽  
Content Type ◽  
Action Mechanisms ◽  
New Compounds

PurposeThis paper aims to prepare a residual rust epoxy coating by adding different quantities of phytic acid (PA) on the surface of the rusty steel and investigate the corrosion protection of PA and its action mechanisms.Design/methodology/approachA residual rust epoxy coating by adding different quantities of PA was prepared on the surface of the rusty steel. The influence of PA on the corrosion resistance of epoxy-coated rusty steel was investigated by means of electrochemical impedance spectroscopy and adhesion testing.FindingsResults indicated that PA can substantially improve the corrosion resistance of epoxy-coated rusty steel. This improvement is due to the reaction of PA with residual rust and generation of new compounds with protection properties and increased adhesive strength effects on the coating/metal interface. The coating showed better protection performance when 2 per cent PA was added.Originality/valueConsidering the structure of the active groups, PA has strong chelating capability with many metal ions and can form stable complex compounds on the surface of a metal substrate, thereby improving corrosion resistance. In recent years, PA has been reported to be useful in the conversion of coatings or as green corrosion inhibitor. To the best of the authors’ knowledge, few studies have reported the use of PA as a rust converter or residual rust coating. The present work aims to improve the corrosion resistance of residual rust epoxy coating by adding PA.

Applicability of EIS for evaluation of corrosion resistance of aluminum flakes

2016 ◽  
Vol 63 (5) ◽  
pp. 355-359
Author(s):  
Naghmeh Amirshaqaqi ◽  
Mehdi Salami-Kalajahi ◽  
Mohammad Mahdavian
Keyword(s):  
Corrosion Resistance ◽  
Conventional Method ◽  
Design Methodology ◽  
Electrochemical Impedance ◽  
Quantitative Estimation ◽  
Surface Modifications ◽  
Organic Coatings ◽  
Nacl Solution ◽  
Content Type ◽  
Alkaline Conditions

Purpose The conventional method for evaluation of corrosion resistance of aluminum flakes is based on the volume of evolved hydrogen in acidic and basic environments. This study aims to introduce electrochemical impedance spectroscopy (EIS) as a method to evaluate corrosion resistance of aluminum flakes. Design/methodology/approach Aluminum flakes with different surface modifications were compressed to build a disk. Then, the disks were examined by EIS in NaCl solution. Also, the corrosion resistance of the flakes was evaluated by the conventional method. Findings The results revealed applicability of EIS for evaluation of corrosion resistance of aluminum flakes. Originality/value Application of EIS to evaluate corrosion resistance of aluminum flakes is novel. As it can provide fast, reliable and quantitative estimation of the corrosion resistance of the aluminum flakes in the 3.5 per cent NaCl solution. This medium is highly encountered for the aluminum flakes used in organic coatings, that is why test in NaCl solution is more convenient compared to the conventional methods using acid and alkaline conditions.

Effects of potassium silicate on corrosion behavior of dacromet coating

2019 ◽  
Vol 66 (6) ◽  
pp. 819-826
Author(s):  
Khashayar Tabi ◽  
Mansour Farzam ◽  
Davood Zaarei
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Automobile Industry ◽  
Electrochemical Impedance ◽  
Salt Spray ◽  
Corrosion Current ◽  
Potassium Silicate ◽  
Coated Steel ◽  
Content Type ◽  
New Information

Purpose Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated steel to improve its corrosion resistance. The purpose of this paper is to study the corrosion behavior of dacromet-coated steel. Design/methodology/approach Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated steel to improve its corrosion resistance. Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and salt spray were carried out. SEM was used to study the morphological appearance of the surface. Findings The EIS behavior indicated that solvent-cleaned dacromet-coated steel sealed with potassium silicate showed that the corrosion current density was 2.664E − 5 A.cm2 which was reduced to 8.752E − 6 A.cm2 and the corrosion rate, which was 2.264E − 2 mm.year−1, was reduced to 7.438E − 3 mm.year−1 in NaCl 3.5 wt.per cent. EIS was used in NaCl 3.5 wt.%, and the Bode plot characteristics showed that the corrosion protection of solvent-cleaned, dacromet-coated steel was enhanced when sealed with potassium silicate. The EDS results of salt-sprayed, solvent-cleaned samples after 10 days indicated that the main corrosion products are composed of SiO2, ZnO and Al2O3. Research limitations/implications The detection of Li element in EDS was not possible because of the device limitation. Originality/value The current paper provides new information about the sealing properties of potassium silicate and its effects on the corrosion resistance of dacromet coating, which is widely used in many industries such as the automobile industry.

Melatonin as an Accelerating Agent for Phosphate Chemical Conversion Coatings on Mild Steel with Enhanced Corrosion Resistance

2020 ◽  
Vol 167 (10) ◽  
pp. 101505
Author(s):  
Yuqin Tian ◽  
Weijun Qiu ◽  
Yuhui Xie ◽  
Haowei Huang ◽  
Jin Hu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Mild Steel ◽  
Chemical Conversion ◽  
Conversion Coatings

Corrosion protective properties of coatings doped with inhibitors

2014 ◽  
Vol 61 (6) ◽  
pp. 416-422 ◽  
Author(s):  
Mansoureh Parsa ◽  
Seyed Mohammad Ali Hosseini ◽  
Zahra Hassani ◽  
Effat Jamalizadeh
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Protection ◽  
Electrochemical Impedance ◽  
Sol Gel ◽  
Titania Nanoparticles ◽  
Self Healing ◽  
Properties Of Coatings ◽  
Ethylene Imine ◽  
Protective Properties ◽  
Content Type

Purpose – The purpose of this paper was to study the corrosion resistance of water-based sol-gel coatings containing titania nanoparticles doped with organic inhibitors for corrosion protection of AA2024 alloy. Design/methodology/approach – The coatings were obtained using tetraethylorthosilicate, 3-glycidoxypropyltrimethoxysilane, titanium (IV) tetrapropoxide and poly(ethylene imine) polymer as cross-linking agents. As corrosions inhibitors, 2-mercaptobenzoxazole and salicylaldoxime were incorporated into the sol-gel for the improvement of the corrosion resistance. The corrosion protection performance of coatings was studied using the potentiodynamic scan and the electrochemical impedance spectroscopy (EIS) methods. Atomic force microscopy was used to investigate surface morphology of the coatings. Findings – The results indicated that doping the sol-gel coatings with inhibitors leads to improvement of the corrosion protection. The comparison of doped coatings confirmed that corrosion protection performance of the sol-gel coatings doped with 2-mercaptobenzoxazole was better than for the sol-gel coatings doped with salicylaldoxime. Also the EIS results verified self-healing effects for the sol-gel coatings doped with 2-mercaptobenzoxazole. Originality/value – This paper indicates 2-mercaptobenzoxazole and salicylaldoxime can be added as corrosion inhibitors to sol-gel coatings to improve their corrosion protective properties for AA2024 alloy.

The passive properties of TA10 in Coca-Cola containing oral environment

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ming Liu ◽  
Jun Li ◽  
Danping Li ◽  
Lierui Zheng
Keyword(s):  
Corrosion Resistance ◽  
Passive Film ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Artificial Saliva ◽  
Corrosion Current ◽  
Content Type ◽  
Passive Behavior ◽  
Tooth Demineralization ◽  
Oral Environment

Purpose At present, carbonated drinks such as cola are especially favored by the younger generation. But because of its acid, it often leads to tooth demineralization, resulting in “cola tooth”. However, the influence of cola on the corrosion resistance of passive film of TiA10 alloy restorative materials is rarely reported. The purpose of this study was to analysis the corrosion resistance, composition of the passive film of TA10 alloy in different concentrations of Cola. Design/methodology/approach The passive behavior of TA10 alloy in artificial saliva (AS) and Cola was studied by means of potentiodynamic polarization, electrochemical impedance spectroscopy, cyclic voltammetry, Mott-Schottky techniques and combined with X-ray photoelectron spectroscopy and Auger electron spectroscopy (AES) surface analysis. Findings With the increase of cola content, the self-corrosion current density of the alloy increases sharply, and the corrosion resistance of the passive film is the best in AS, while Rp in cola is reduced to half of that in AS. The thickness of the passive film in AS, AS +cola and cola is about 9.5 nm, 7.5 nm and 6 nm, respectively. The passive film in cola has more defects and the carrier density is 1.55 times as high as that in AS. Cola can weaken the formation process of the protected oxide, promote the formation of high valence Ti-oxides and increase the content of Mo-oxides in the passive film. Originality/value These results have important guiding significance for the safe use of the alloy in the complex oral environments.

scholarly journals Corrosion behavior in Ringer solution of several commercially used metal alloys

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Carmen Marina Garcia-Falcon ◽  
Tomas Gil-Lopez ◽  
Amparo Verdu-Vazquez ◽  
Julia Claudia Mirza-Rosca
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Dental Materials ◽  
Ringer Solution ◽  
Open Circuit ◽  
Metal Alloys ◽  
Cylindrical Shape ◽  
Content Type ◽  
Biological Safety

Purpose This paper aims to analyze the corrosion behavior in Ringer solution of six commercially used Ni-based alloys that are present and commonly used as metallic biomaterials. Design/methodology/approach The specimens were received in the form of cylindrical ingots and were cut to get five samples of each brand with a cylindrical shape of 2 mm height to conduct the study. In this scientific research, the following techniques were used: open circuit potential, potentiodynamic polarization studies, and electrochemical impedance spectroscopy. Findings The study findings revealed the passivation tendency of the different specimens. Additionally, when the materials were compared, it was discovered that the decisive factor for high corrosion resistance was the chromium concentration. However, with similar chromium content, the stronger concentration in molybdenum increased the resistance. According to the results obtained in this investigation, the biological safety of the dental materials studied in Ringer solution was considered very high for specimens 1 and 2, and adequate for the other samples. Originality/value Metal alloys used as biomaterials in contact with the human body should be deeply investigated to make sure they are biocompatible and do not cause any harm. The corrosion resistance of an alloy is the most important characteristic for its biological safety, as all problems arise because of the corrosion process. There is scarce investigation in these Ni-based dental biomaterials, and none found in these commercially used dental materials in Ringer solution.

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