Effect of PEO Coating Microstructure on Corrosion of Al 2024

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	Effect of PEO Coating Microstructure on Corrosion of Al 2024
	K. Q. Du; X. H. Guo; Q. Z. Guo; Y. Wang; F. H. Wang; Y. Tian
	2012
发表期刊	Journal of the Electrochemical Society
ISSN	0013-4651
卷号	159 期号:12 页码:C597-C606
摘要	Transient self-feedback control (TSFC) was employed to prepare plasma electrolytic oxidation (PEO) coatings on 2024 Al alloy. Compared with Al2O3 PEO coating by the custom pulse voltage (CPV) process, the PEO coating using the TSFC mode generated a thinner outer layer and more compact inner layer. In order to study the microstructure effect on the practical corrosion properties, three Al2O3 PEO coatings using the CPV and TSFC processes were studied during long term immersion in a corrosive environment by electrochemical impedance spectroscopy (EIS) and neutral salt spray test (NSST). Two groups of electrical equivalent circuits were employed based on different microstructures. During the initial immersion period a double-layer element (CPEdl /R-t) appeared due to the CPV PEO coating having a porous outer layer and thinner inner layer. Thereafter, continuous corrosion reactions happened at the metal/PEO interface, which resulted in the appearance of diffusion elements. However, for specimens prepared by TSFC, corrosion reactions only happened in the later stages of the immersion. The compact and thick inner layer mainly contributed to excellent barrier properties. stable microstructure after 380 h immersion in 3.5(wt%) NaCl solution and excellent performance in the salt spray test. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.005301jes] All rights reserved.
部门归属	[du, keqin; guo, xinghua; guo, quanzhong; wang, yong; wang, fuhui] chinese acad sci, inst met res, state key lab corros & protect, shenyang, peoples r china. [tian, ying] dalian jiaotong univ, coll environm & chem engn, dalian, peoples r china.;du, kq (reprint author), chinese acad sci, inst met res, state key lab corros & protect, shenyang, peoples r china.;kqdu@imr.ac.cn; xhguo@imr.ac.cn
关键词	Plasma Electrolytic Oxidation Electrochemical Impedance Spectroscopy Different Paint Systems Micro-arc Oxidation Aluminum-alloy Ceramic Coatings Barrier Properties Nacl Solution Water-uptake Conversion Coatings
URL	查看原文
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/59934
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	K. Q. Du,X. H. Guo,Q. Z. Guo,et al. Effect of PEO Coating Microstructure on Corrosion of Al 2024[J]. Journal of the Electrochemical Society,2012,159(12):C597-C606.
APA	K. Q. Du,X. H. Guo,Q. Z. Guo,Y. Wang,F. H. Wang,&Y. Tian.(2012).Effect of PEO Coating Microstructure on Corrosion of Al 2024.Journal of the Electrochemical Society,159(12),C597-C606.
MLA	K. Q. Du,et al."Effect of PEO Coating Microstructure on Corrosion of Al 2024".Journal of the Electrochemical Society 159.12(2012):C597-C606.