Effect of the direct current electric field on the initial corrosion of steel in simulated industrial atmospheric environment

• Published in: Corrosion science Vol. 99; pp. 295 - 303
• Main Authors: Dai, Nianwei, Zhang, Junxi, Chen, Qimeng, Yi, Bo, Cao, Fahe, Zhang, Jianqing
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2015
• Subjects: A. Steel; B. Polarization; B. SEM; B. X-ray diffraction; C. Atmospheric corrosion; B. SEM; B. X-ray diffraction; C. Atmospheric corrosion; A. Steel; B. Polarization
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2015.07.029

•Effect of DC electric field on corrosion products formed on steel was investigated.•Corrosion rate increased with the increase of DC electric field intensity.•DC electric field suppressed the growth of α-FeOOH and favoured the yield of γ-FeOOH.•DC electric field affected the composition and structure of corrosion products. The effects of the direct current (DC) electric field on the initial corrosion of steel in simulated solution were investigated using measurements of weight loss and polarization curves, XRD and SEM techniques. The major constituents of the corrosion products are α- and γ-FeOOH in SO42− solution. It was found that the corrosion rate of steel increased with the increase of DC electric field intensity. And the DC electric field suppresses the growth of α-FeOOH and the transformation of γ-FeOOH to α-FeOOH. All these lead to the reduction of the protective ability of rust layer and accelerate further corrosion of steel.