Microstructure and properties of ceramic coatings prepared by micro-arc oxidation on 7075 aluminum alloy

Purpose The purpose of this is to study the effects of organic sealing on the structure and performance of the micro-arc oxidation (MAO) film of 7075 aluminum alloy. Design/methodology/approach The 7075 aluminum alloy was treated by micro-arc oxidation technology, then the MAO films were sealed by polyvinylidene fluoride (PVDF) solutions with different concentrations to forms a MAO/PVDF composite coating on the surface of the 7075 aluminum alloy matrix. Findings The results show that the MAO/PVDF film thickness increased to 24.8 um. When the PVDF concentration was 8 g/L, and the sealed film reached best corrosion resistance and wear resistance. Originality/value The effects of different concentrations of PVDF on microarc oxidation properties of 7075 aluminum alloy were studied.

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Effects of graphene on the microstructure and properties of MAO coatings formed on AA7050

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2020-1110603 ◽

2020 ◽

Vol 111 (6) ◽

pp. 463-468

Author(s):

Bo Xu ◽

Yafeng He ◽

Xiangzhi Wang ◽

Weimin Gan

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Corrosion Resistance ◽

Aluminum Alloy ◽

Composite Coatings ◽

Ceramic Coatings ◽

X Ray Diffraction ◽

X Ray ◽

Micro Arc Oxidation ◽

Scanning Electron

Abstract Ceramic coatings were prepared on the surface of 7050 highstrength aluminum alloy using micro-arc oxidation in an aluminate electrolyte with added graphene. To analyze the surface morphology, roughness, phase composition, and corrosion resistance, scanning electron microscopy, X-ray diffraction, X-ray photoelectron, and electrochemical measurements were used, respectively. The addition of 9 g · L-1 of graphene to the electrolyte decreased the micro-pore size of the composite coatings and improved the density. In addition, with the addition of graphene, the roughness was the lowest, and the corrosion resistance was significantly improved.

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Influence of cathodic current density on properties of ceramic coatings on 6063 aluminum alloy by micro-arc oxidation×

International Journal of Electrochemical Science ◽

10.20964/110431 ◽

2016 ◽

pp. 3296-3310 ◽

Cited By ~ 1

Author(s):

Song Chen ◽

Keyword(s):

Aluminum Alloy ◽

Current Density ◽

Ceramic Coatings ◽

Cathodic Current Density ◽

Cathodic Current ◽

Micro Arc Oxidation ◽

6063 Aluminum Alloy

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Effects of Al2O3 Nanoparticles on Microstructure and Performance of Ceramic Coatings by Micro-Arc Oxidation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.537.92 ◽

2013 ◽

Vol 537 ◽

pp. 92-96

Author(s):

Yu Jun Yin ◽

Shu Hua Li ◽

Da Wei Shen ◽

Yuan Yuan Zu ◽

Chang Zheng Qu

Keyword(s):

Aluminum Alloy ◽

Oxide Coating ◽

Ceramic Coatings ◽

Al2o3 Nanoparticles ◽

Electrolytic Solution ◽

Dense Ceramic ◽

Micro Arc Oxidation ◽

And Performance ◽

Microstructure And Performance ◽

Ceramic Oxide Coating

A dense ceramic oxide coating approximately 45 µm thick was prepared on a Ly12 aluminum alloy by micro-arc oxidation in an alkali-phosphate electrolytic solution. Coating thickness and surface roughness (Ra) were measured after the coating had been synthesized. The effects of Al2O3 Nanoparticles in electrolyte on phase composition, microstructure and microhardness of the micro-arc oxidation ceramic coatings on Ly12 aluminum alloy were investigated by means of XRD, SEM and hardness experimentation. The results show that the ceramic coatings become more dense and its microhardness increased by adding Al2O3 Nanoparticles in electrolyte. In addition, the roughness of the micro-arc oxidation ceramic coatings is obviously improved by addition of Al2O3 Nanoparticles.

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Effect of Current Density on the Microstructure and Corrosion Properties of MAO Coatings on Aluminum Alloy Shock Absorber

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.764.28 ◽

2018 ◽

Vol 764 ◽

pp. 28-38 ◽

Cited By ~ 1

Author(s):

Yan Shen ◽

Hong Xiang Wang ◽

Yi Peng Pan

Keyword(s):

Corrosion Resistance ◽

Aluminum Alloy ◽

Current Density ◽

Shock Absorber ◽

Structural Characteristics ◽

Ceramic Coatings ◽

Corrosion Performance ◽

Cathode Voltage ◽

Corrosion Properties ◽

Micro Arc Oxidation

In order to improve the corrosion resistance of shock absorber for ships, the alumina ceramic coatings are carried out on the surface of aluminum alloy shock absorber by micro arc oxidation (MAO) technology. The microstructure and anti-corrosion performance of the MAO coatings were investigated experimentally. This paper mainly focuses on the experimental work to determine the effect of current density on the structural characteristics and corrosion resistance of MAO coatings. The results show that the current density has a significant influence on the preparation of MAO coating during the process. The surface of the coating becomes more compact and smooth with the cathode voltage of 7 A.dm-2. Furthermore, the anti-corrosion performance of the MAO coatings can effectively be improved at the current density of 7 A.dm-2.

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