MICROSTRUCTURE AND ELECTROCHEMICAL PROPERTIES OF Ni–B/GO ULTRASONIC-ASSISTED COMPOSITE COATINGS

2019 ◽  
Vol 26 (10) ◽  
pp. 1950080
Author(s):  
JIBO JIANG ◽  
HAOTIAN CHEN ◽  
LIYING ZHU ◽  
YAOXIN SUN ◽  
WEI QIAN ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Composite Coatings ◽  
Ultrasonic Field ◽  
Protective Material ◽  
X Ray ◽  
Electrochemical Tests ◽  
Ultrasonic Assisted ◽  
Corrosive Environments

Graphene oxide (GO) sheet and ultrasonic field (UF) were successfully employed to produce Ni–B/GO and UF–Ni–B/GO composite coatings on Q235 mild steel by electroless plating. The composite coatings’ structure and surface morphology were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Results showed that GO was successfully co-deposited in the Ni–B alloy. Moreover, UF–Ni–B/GO composite coatings have smoother surface and thicker cross-section than others. The microhardness and corrosion resistance of the sample coatings were determined using Vickers hardness tests, Tafel electrochemical tests and electrochemical impedance measurements (EIS) in 3.5[Formula: see text]wt.% NaCl solution to receive the effect of GO and ultrasonic. The findings indicated that UF–Ni–B/GO exhibited optimum hardness (856[Formula: see text]HV) and enhanced corrosion resistance (6.38 [Formula: see text][Formula: see text] over the Ni–B and Ni–B/GO coatings. Due to these interesting properties of the coating, it could be used as a protective material in the automotive and aerospace industries for parts of machines that were manipulated in high temperature and corrosive environments.

Effect of Nano-Al2O3 Particles on the NiP/nano-Al2O3 Coatings’ Properties

2011 ◽  
Vol 66-68 ◽  
pp. 1668-1675 ◽  
Author(s):  
Xue Tao Yuan ◽  
Zhi Qiang Hua ◽  
Lei Wang ◽  
Dong Bai Sun ◽  
Song Lin Chen
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Composite Coatings ◽  
Electroless Nickel ◽  
Nano Particles ◽  
X Ray Diffraction ◽  
Regular Surface ◽  
X Ray ◽  
Electrochemical Tests ◽  
Better Than

Composite coatings were prepared using electroless nickel bath containing different concentrations of Al2O3nano-particles. The analyses of coating compositions, carried out by EDS, showed that there is marginal difference between phosphorus contents of NiP and NiP/nano-Al2O3deposits. The structure of the coatings was examined by scanning electron microscopy (SEM), and X-ray diffraction (XRD). It has been found that the co-deposition of nano-Al2O3particles with Ni disturbs the NiP coating’s regular surface structure and increases its surface roughness. DC and AC electrochemical tests were carried out on such coatings in a 3.5wt.% solution of NaCl in order to evaluate their corrosion resistance. The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests both showed that, the corrosion resistance of NiP-Al2O3coatings firstly increases and then decreases when Al2O3concentration in electroless bath is increasing, but the corrosion resistance of NiP-Al2O3composite coating is better than that of amorphous NiP coating.

scholarly journals Composition and Performance of Nanostructured Zirconium Titanium Conversion Coating on Aluminum-Magnesium Alloys

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Sheng-xue Yu ◽  
Rui-jun Zhang ◽  
Yong-fu Tang ◽  
Yan-ling Ma ◽  
Wen-chao Du
Keyword(s):  
Corrosion Resistance ◽  
Salt Solution ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Impedance Spectrum ◽  
Conversion Coating ◽  
Mg Alloy ◽  
Electrochemical Impedance Spectrum ◽  
X Ray ◽  
Titanium Salt

Nanostructured conversion coating of Al-Mg alloy was obtained via the surface treatment with zirconium titanium salt solution at 25°C for 10 min. The zirconium titanium salt solution is composed of tannic acid 1.00 g·L−1, K2ZrF60.75 g·L−1, NaF 1.25 g·L−1, MgSO41.0 g/L, and tetra-n-butyl titanate (TBT) 0.08 g·L−1. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrum (FT-IR) were used to characterize the composition and structure of the obtained conversion coating. The morphology of the conversion coating was obtained by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results exhibit that the zirconium titanium salt conversion coating of Al-Mg alloy contains Ti, Zr, Al, F, O, Mg, C, Na, and so on. The conversion coating with nm level thickness is smooth, uniform, and compact. Corrosion resistance of conversion coating was evaluated in the 3.5 wt.% NaCl electrolyte through polarization curves and electrochemical impedance spectrum (EIS). Self-corrosion current density on the nanostructured conversion coating of Al-Mg alloy is9.7×10-8A·cm-2, which is only 2% of that on the untreated aluminum-magnesium alloy. This result indicates that the corrosion resistance of the conversion coating is improved markedly after chemical conversion treatment.

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.

scholarly journals Enhanced Corrosion Resistance of SiCp/ 2009 Al by Cerium and Lanthanum Conversion Treatment

2018 ◽  
Vol 778 ◽  
pp. 251-255
Author(s):  
Irfan Aziz ◽  
Qi Zhang
Keyword(s):  
Corrosion Resistance ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Localized Corrosion ◽  
Al Alloy ◽  
Unreinforced Alloy ◽  
Maximum Increase ◽  
X Ray ◽  
Eds Analysis ◽  
Polarization Studies

The present study investigates the effect of lanthanide chlorides conversion coatings on the corrosion response of the 2009 Al alloy and SiCp reinforced 2009 Al MMCs. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization studies showed that the localized corrosion resistance increased after treatments with solutions having various combinations of CeCl3.7H2O and LaCl3.7H2O, with maximum increase noticed for 5000ppm CeCl3.7H2O. It was found that the protection degree effect obtained under similar coating conditions for 25 vol.% SiCp/2009 Al was relatively higher than 15vol.% SiCp/ 2009 Al MMC, but both of them were less than that of the unreinforced alloy. Scanning electron microscopy (SEM) accompanied with energy dispersive spectroscopy (EDS) analysis revealed the deposition of Ce and/ or La oxides/ hydroxides on cathodic intermetallics/ SiCp and the existence of crevices at the SiCp/ matrix interfaces. X-ray photoelectron spectroscopy (XPS) results indicated that Ce was incorporated as Ce3+ and Ce4+ species in the coatings.

Preparation and properties of natural gallic acid based rust conversion emulsion

2016 ◽  
Vol 45 (3) ◽  
pp. 191-198 ◽  
Author(s):  
Yuanfeng Jia ◽  
Nana Ren ◽  
Huadong Yue ◽  
Jianru Deng ◽  
Yali Liu
Keyword(s):  
Raman Spectroscopy ◽  
Corrosion Resistance ◽  
Gallic Acid ◽  
Photoelectron Spectroscopy ◽  
High Efficiency ◽  
Hydroxyl Groups ◽  
Content Type ◽  
X Ray ◽  
Electrochemical Tests ◽  
Emulsion Polymerisation

Purpose The paper developed a novel gallic acid-based rust conversion emulsion (RCE) that is applied in the treatment of rusted steels. The purpose of this paper is to investigate the methods for the synthesis of RCE and study the mechanism of rust conversion. Design/methodology/approach Conversion emulsion was prepared using styrene, acrylate and self-developed gallic acid (GA)-based rust converter (GRC) via seed emulsion polymerisation. The polymerisable GRC was synthesised by the ring-opening reaction of glycidyl methacrylate with natural GA. The effects of the GRC dosage and its feeding modes on the RCE synthesis were analysed. The corrosion resistance, surface morphology, composition and mechanism of rust conversion coatings were studied using electrochemical tests, scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively. Findings The results showed that conversion coating on rusted steels treated with RCE, with various dosages of GRC (weight per cent), synthesised using seed emulsion polymerisation, exhibited the best adhesion and corrosion resistance. Raman spectroscopy revealed that RCE converted the original multiphase rust into stable crystalline phases of α-Fe2O3 and Fe3O4. According to XPS and energy dispersive X-ray analysis, the phenolic hydroxyl groups of RCE were proposed to chelate with Fe ions to form macromolecular ferrum compounds. Research limitations/implications The pre-rusted steels demonstrated a better corrosion resistance than rust-free steels after treatment with RCE. Practical implications The paper developed a novel GA-based RCE with high efficiency and environment-friendly method. Originality/value This work is expected to replace the conventional rust conversion paints and cause a significant impact on extending the service life of rusted steels.

Corrosion Behavior and Microstructure of Pd Ions Doped Cerium Conversion Coating on AA2219-T87 Aluminum Alloy

2015 ◽  
Vol 1090 ◽  
pp. 79-83
Author(s):  
Yan Hong He ◽  
Zhen Duo Cui ◽  
Xian Jin Yang ◽  
Sheng Li Zhu ◽  
Zhao Yang Li ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Corrosion Behavior ◽  
Photoelectron Spectroscopy ◽  
Composite Coatings ◽  
Corrosion Current ◽  
Conversion Coating ◽  
X Ray Diffraction ◽  
X Ray ◽  
Excellent Corrosion Resistance

In this paper, Pd ions doped cerium conversion coating (CeCC/Pd) was deposited on AA2219-T87 aluminum alloy by electroplating. The microstructure and composition of the coating were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). Corrosion behavior of AA2219-T87 aluminum alloy with the coating was investigated in 3.5wt.% NaCl solution at the room temperature. XRD and XPS results indicate the existence of cerium-oxide and palladium-oxide in the CeCC/Pd. Polarization curves show that the CeCC/Pd exhibits excellent corrosion resistance. The corrosion current density of the CeCC/Pd decreases by two orders of magnitude compared with the CeCC. The improvement of corrosion resistance would be attributed to the small grain size, good compactness and adhesive strength of the composite coatings.

scholarly journals Electrochemical Performance of Fe40Al-X (X = Cr, Ti, Co, Ni) Alloys Exposed to Artificial Saliva

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1095
Author(s):  
Cinthya Dinorah Arrieta-Gonzalez ◽  
Roberto Ademar Rodriguez-Diaz ◽  
Jan Mayen ◽  
Rogel Fernando Retes-Mantilla ◽  
María Teresa Torres-Mancera ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Performance ◽  
Electrochemical Impedance ◽  
Artificial Saliva ◽  
Alloy Element ◽  
Passive Layer ◽  
Open Circuit ◽  
Intermetallic Alloys ◽  
Electrochemical Tests ◽  
Corrosive Environments

Fe–Al intermetallic compounds have been considered excellent candidates as alternative alloys for various applications in corrosive environments compared to other Fe-based alloys. Their excellent corrosion resistance is due to the development of an Al-based passive layer. The performance of the passive layer can be improved by adding a third alloy element. Therefore, in this study the electrochemical performance of the Fe40Al intermetallic alloy modified by the addition of a third alloy element (Cr, Ti, Co, Ni) is evaluated. The corrosion resistance of intermetallic alloys has been evaluated by electrochemical tests (potentiodynamic polarization curves, and measurements of open circuit potential, linear polarization and electrochemical impedance) in artificial saliva. The performance of intermetallic alloys was compared with that of Ti. The results obtained showed that the addition of Ni and Ti substantially improves the corrosion resistance of the base intermetallic. The corrosion resistance shown is comparable or greater than that shown by Ti. However, the addition of Co reduces the corrosion resistance of the base intermetallic.

scholarly journals The Influence of Microstructure on the Passive Layer Chemistry and Corrosion Resistance for Some Titanium-Based Alloys

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1233 ◽  
Author(s):  
Nader El-Bagoury ◽  
Sameh I. Ahmed ◽  
Ola Ahmed Abu Ali ◽  
Shimaa El-Hadad ◽  
Ahmed M. Fallatah ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Pitting Corrosion ◽  
Photoelectron Spectroscopy ◽  
Volume Fraction ◽  
Electrochemical Impedance ◽  
Passive Layer ◽  
Layer Growth ◽  
Uniform Corrosion ◽  
Cyclic Polarization ◽  
X Ray

The effect of microstructure and chemistry on the kinetics of passive layer growth and passivity breakdown of some Ti-based alloys, namely Ti-6Al-4V, Ti-6Al-7Nb and TC21 alloys, was studied. The rate of pitting corrosion was evaluated using cyclic polarization measurements. Chronoamperometry was applied to assess the passive layer growth kinetics and breakdown. Microstructure influence on the uniform corrosion rate of these alloys was also investigated employing dynamic electrochemical impedance spectroscopy (DEIS). Corrosion studies were performed in 0.9% NaCl solution at 37 °C, and the obtained results were compared with ultrapure Ti (99.99%). The different phases of the microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Chemical composition and chemistry of the corroded surfaces were studied using X-ray photoelectron spectroscopy (XPS) analysis. For all studied alloys, the microstructure consisted of α matrix, which was strengthened by β phase. The highest and the lowest values of the β phase’s volume fraction were recorded for TC21 and Ti-Al-Nb alloys, respectively. The susceptibility of the investigated alloys toward pitting corrosion was enhanced following the sequence: Ti-6Al-7Nb < Ti-6Al-4V << TC21. Ti-6Al-7Nb alloy recorded the lowest pitting corrosion resistance (Rpit) among studied alloys, approaching that of pure Ti. The obvious changes in the microstructure of these alloys, together with XPS findings, were adopted to interpret the pronounced variation in the corrosion behavior of these materials.

scholarly journals Preparation and Anti-Corrosive Properties of Waterborne Epoxy Composite Coating Containing Graphene Oxide Grafted with Sodium Tripolyphosphate

Coatings ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 307 ◽  
Author(s):  
Na Wang ◽  
Xu Yin ◽  
Jing Zhang ◽  
Huiying Gao ◽  
Xinlin Diao ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Sodium Tripolyphosphate ◽  
Salt Spray ◽  
Salt Spray Test ◽  
Coated Sample ◽  
X Ray ◽  
Waterborne Epoxy

In this paper, graphene oxide (GO) was grafted with sodium tripolyphosphate (STP) to achieve a new anti-corrosive pigment (STG) with homogenous dispersion in waterborne epoxy (EP). The results obtained from Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and X-ray Diffraction (XRD) revealed that STP was successfully combined with GO by chemical bonding. The corrosion resistance of EP, GO/EP and STG/EP coatings on carbon steel substrates was investigated via electrochemical impedance spectroscopy (EIS) and salt spray test. The EIS results showed that the impedance value of coating with 0.7 wt.% STG reached 1.019 × 109 Ω∙cm2, which was considerably higher than that of neat waterborne EP coatings. Salt spray test results revealed once again that STG (0.7 wt.%)/EP coating had superior corrosion resistance. Besides, the STG (0.7 wt.%)/EP coated sample showed the highest adhesion strength between coating and substrate.

scholarly journals Microstructure and Corrosion Resistance of WC-Based Cermet/Fe-Based Amorphous Alloy Composite Coatings

Coatings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 393 ◽  
Author(s):  
Liping Xu ◽  
Jinbing Song ◽  
Xiaofeng Zhang ◽  
Changguang Deng ◽  
Min Liu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Amorphous Alloy ◽  
Composite Coating ◽  
Composite Coatings ◽  
Alloy Composite ◽  
Electrochemical Tests ◽  
Transmission Electron ◽  
Alkaline Electrolytes ◽  
Naoh Solution ◽  
Corrosive Environments

There is an urgent need to improve the corrosion resistance of WC-based cermet coatings in different corrosive environments. The main objective of this work was to investigate the microstructure and evaluate the corrosion resistance in neutral, acidic, and alkaline electrolytes of the WC-based cermet/Fe-based amorphous alloy composite coating. Thus, a composite coating of WC–CoCr/Fe-based amorphous alloy and a single WC–CoCr coating were fabricated using the high-velocity oxygen fuel (HVOF) process. The phase composition, microstructure of the original powders, and as-sprayed coatings were studied. The detailed interface information between different compositions of the composite coating was observed by high-resolution transmission electron microscopy (HRTEM). The corrosion resistance of the coatings was studied comparatively by electrochemical tests in 3.5 wt % NaCl, 1 M HCl and 1 M NaOH solutions, respectively. Results showed that the composited coating had a dense layered structure with a composition of WC, Fe-based amorphous alloy, and small amount of W2C. It was revealed that obvious inter-diffusion exists between the interfaces of tungsten carbide/Co, Cr binder and WC–CoCr/Fe-based amorphous alloy. The electrochemical test results showed that the composite coating displayed better corrosion resistance than single WC–CoCr coating both in 3.5 wt % NaCl solution and in 1 M NaOH solution.

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