In Situ SECM Observation of Corrosion Behavior of Carbon Steel at Defects of Epoxy Coating under AC Current Conditions

被引：0

作者：

Gong W. ^{[1
]}

Yang B. ^{[2
]}

Chen Y. ^{[2
]}

Hao W. ^{[2
]}

Wang X. ^{[2
]}

Chen H. ^{[1
]}

机构：

[1] Inner Mongolia Power Research Institute, Hohhot

[2] State Key Laboratory of Advanced Transmission Technology, Global Energy Interconnection Research Institute, Beijing

来源：

Yang, Bingkun (ybk_511@163.com) | 1600年 / Chinese Journal of Materials Research卷 / 34期

关键词：

AC current; Carbon steel; Corrosion; In situ; Materials failure and protection;

D O I：

10.11901/1005.3093.2019.571

中图分类号：

学科分类号：

摘要：

The carbon steel corrosion behavior at defects of epoxy coating in the effect of different AC current densities was investigated by means of in situ micro-area electrochemistry and traditional macro-electrochemical techniques, namely electrochemical scanning microscopy (SECM) and electrochemical impedance spectroscopy techniques. SECM observation can directly reveal the change of electrochemical active points during the local corrosion process of carbon steel at coating defects. The results show that when AC current is present, the number of corrosion active points at the coating defects is significantly more than that in the absence of AC current, correspondingly, the inhibitory effect of the corrosion products is significantly weaker than that in the case without AC current. The corrosion at the coating defect at the initial stage of immersion is an electron transfer control process, and it is converted to a diffusion control process after soaking for 10 hours. With the increase of AC current intensity and immersion time the degree of coating peeling increases, and the depth and width of the pits increase. © All right reserved.

引用

页码：545 / 553

页数：8

共 21 条

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