Effect of process parameters on corrosion resistance of MAO/LDH composite coatings

被引：0

作者：

Li Y. ^{[1
]}

Zhang Q.-Y. ^{[1
]}

Lu X.-P. ^{[1
]}

Zhang T. ^{[1
]}

Wang F.-H. ^{[1
]}

机构：

[1] Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang

来源：

Surface Technology | 2021年 / 50卷 / 08期

基金：

中国国家自然科学基金;

关键词：

Corrosion resistance; Hydrophobicity; Layered double hydroxide; Magnesium alloy; Micro-arc oxidation;

D O I：

10.16490/j.cnki.issn.1001-3660.2021.08.031

中图分类号：

学科分类号：

摘要：

The work aims to improve the corrosion resistance of the micro-arc oxidation (MAO) coatings by layered double hydroxide (LDH). Firstly, the MAO coatings of Mg alloy were prepared in silicate, phosphate and aluminate-based electrolytes. Then the LDH was grown in situ on surface of MAO coatings. The samples were immersed in an autoclave and mixed with aluminum nitrate and zinc nitrate solution. Scanning electron microscopy, XRD, water contact angle measuring system and electrochemical corrosion tests were used to explore the micromorphology, composition and corrosion resistance of the coatings. The experimental results show that the LDH layer formed in aluminate system is thick and dense, while the amount of hydrotalcite was small and micro-pores and micro-cracks of MAO coatings were not completely closed by LDH in silicate and phosphate system. The results of XRD indicated that LDH had grown in situ on surface of MAO coatings. In silicate system, the contact angles of the composite coatings prepared under 400 V and 430 V conditions were 74.3° and 130.3°, respectively. The composite coating prepared in phosphate and aluminate has a low contact angle, without a hydrophobic. In silicate system, the composite coating prepared at 430 V has an impedance modulus of composite film of 2×107 Ω‧cm2, with the corrosion resistance increasing by about 10 times. In situ LDH has a great influence on the corrosion resistance of the coating, and the voltage has no significant influence on the LDH. © 2021, Chongqing Wujiu Periodicals Press. All rights reserved.

引用

页码：327 / 336

页数：9

共 32 条

[1]

Esmaily M., Svensson J E., Fajardo S., Et al., Fundamentals and advances in magnesium alloy corro-sion[J], Progress in Materials Science, 89, pp. 92-193, (2017)

[2]

Ambat R., Aung N.N., Zhou W., Evaluation of microstructural effects on corrosion behaviour of AZ91D magnesium alloy[J], Corrosion Science, 42, 8, pp. 1433-1455, (2000)

[3]

Gomes M P., Costa I., Pebere N., Et al., On the corrosion mechanism of Mg investigated by electrochemical impedance spectroscopy[J], Electrochimica Acta, 306, pp. 61-70, (2019)

[4]

Luan Ji-Yu W.A.N.G.B.-J., Shi-Dong W.A.N.G., Et al., Research progress on stress corrosion cracking behavior of magnesium alloys[J], Journal of Chinese Society for Corrosion and Protection, 39, 2, pp. 89-95, (2019)

[5]

Zhang Xin-Fang L.I.U.L., Jing-Lei L.E.I., Et al., Self-cleaning and self-healing protective coating on magnesium alloy[J], Surface Technology, 48, 3, pp. 27-33, (2019)

[6]

Song Guang-Ling Z.H.U.L.-Q., Improved corrosion resistance of AZ91D magnesium alloy by an aluminium-alloyed coating[J], Surface and Coatings Technology, 200, 8, pp. 2834-2840, (2006)

[7]

Heakal F.E.T., Shehata O.S., Tantawy N.S., Enhanced corrosion resistance of magnesium alloy AM60 by cerium(III) in chloride solution[J], Corrosion Science, 56, pp. 86-95, (2012)

[8]

Yerokhin A L., Nie X., Leyland A., Et al., Plasma electrolysis for surface engineering[J], Surface and Coatings Technology, 122, 2-3, pp. 73-93, (1999)

[9]

Lu Xiao-Peng S.A.H.S.P., Scharnagl N., Et al., Degradation behavior of PEO coating on AM50 magnesium alloy produced from electrolytes with clay particle addition[J], Surface and Coatings Technology, 269, pp. 155-169, (2015)

[10]

Dan L.I.U., En-Hou H.A.N., Ying-Wei S.O.N.G., Et al., Enhancing the self-healing property by adding the synergetic corrosion inhibitors of Na<sub>3</sub>PO<sub>4</sub> and 2-mercaptobenzothiazole into the coating of Mg alloy[J], Electrochimica Acta, 323, (2019)

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