Insight into the corrosion evolution of Fe-based amorphous coatings under wet-dry cyclic conditions

doi:10.1016/j.electacta.2019.07.058

CORC > 金属研究所 > 中国科学院金属研究所

	Insight into the corrosion evolution of Fe-based amorphous coatings under wet-dry cyclic conditions
	Wu, J.1,2; Cui, J. P.1; Zheng, Q. J.2,3; Zhang, S. D.1; Sun, W. H.1; Yang, B. J.1; Wang, J. Q.1
刊名	ELECTROCHIMICA ACTA
	2019-10-01
卷号	319 页码:966-980
关键词	Amorphous coating EIS Wet-dry cyclic test Thin electrolyte film Localized corrosion
ISSN号	0013-4686
DOI	10.1016/j.electacta.2019.07.058
通讯作者	Wang, J. Q.(jqwang@imr.ac.cn)
英文摘要	Understanding the corrosion behavior of Fe-based amorphous coatings under wet-dry cyclic conditions is of pretty importance for coating applications in marine environments. In this paper, the corrosion evolutions of the coatings under wet-dry cyclic conditions were investigated by electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM) and transmission electron microscopy (TEM). Accurate charge transfer resistance (R-t) was obtained through fitting EIS results using a modified transmission line equivalent circuit model and a landscape map of Rt was constructed for a panoramic investigation on coating corrosion. The results show that the corrosion rate of the coating changes cyclically under wet-dry cyclic conditions. Corrosion within a single wet-dry cycle can be presented as four stages: an initial decrease of corrosion rate due to passivation or repassivation when the coating is wetted, then a slow increase due to concentrated aggressive ions with solution evaporation, followed by a rapid increment associated with fast oxygen transport under ultrathin solution film and finally a stable stage as solution dries out. It is deduced that an oxygen concentration gradient can form between the inside and the outside of coating pores when the solution film over the coating is very thin, which further promotes the localized corrosion in the pores. According to the landscape map of R-t, the coating maintains its high corrosion resistance for the initial 33 wet-dry cycles. But its corrosion resistance decreases significantly in the 35th wet-dry cycle accompanied by the attack of localized corrosion. After 65 wet dry cycles, the coating fails due to the penetration of localized corrosion. The interparticle oxide layers are defective, which enhances the localized corrosion process. (C) 2019 Elsevier Ltd. All rights reserved.
资助项目	National Key Research and Development Program of China[2016YFB1100204] ; National Natural Science Foundation of China[51701214] ; National Natural Science Foundation of China[51771195]
WOS研究方向	Electrochemistry
语种	英语
出版者	PERGAMON-ELSEVIER SCIENCE LTD
WOS记录号	WOS:000480706000098
资助机构	National Key Research and Development Program of China ; National Natural Science Foundation of China
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/135040]
专题	金属研究所_中国科学院金属研究所
通讯作者	Wang, J. Q.
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Liaoning, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, Shenyang 110016, Liaoning, Peoples R China 3.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Liaoning, Peoples R China
推荐引用方式 GB/T 7714	Wu, J.,Cui, J. P.,Zheng, Q. J.,et al. Insight into the corrosion evolution of Fe-based amorphous coatings under wet-dry cyclic conditions[J]. ELECTROCHIMICA ACTA,2019,319:966-980.
APA	Wu, J..,Cui, J. P..,Zheng, Q. J..,Zhang, S. D..,Sun, W. H..,...&Wang, J. Q..(2019).Insight into the corrosion evolution of Fe-based amorphous coatings under wet-dry cyclic conditions.ELECTROCHIMICA ACTA,319,966-980.
MLA	Wu, J.,et al."Insight into the corrosion evolution of Fe-based amorphous coatings under wet-dry cyclic conditions".ELECTROCHIMICA ACTA 319(2019):966-980.