The effect of nickel on corrosion behaviour of high-strength low alloy steel rebar in simulated concrete pore solution. (20th June 2020)

• Record Type: Journal Article
• Authors: Tian, Yuwan; Dong, Chaofang; Wang, Gui; Cheng, Xuequn; Li, Xiaogang
• Is Part Of: Construction & building materials. Volume 246(2020)
• Publication Date: 2020-06-20
• Subjects: Nickel -- Steel reinforcement -- Corrosion -- Film -- Composition; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.118462
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Nickel improves corrosion resistance of steel in contaminated concrete. Nickel does not change semiconducting property of oxide film. Nickel promotes formation of compact and thin oxide film. Nickel increases thickness of inner Fe 2+ -rich oxide layer. Abstract: The effect of nickel on the corrosion behaviour of high-strength low alloy steel reinforcement was investigated by electrochemical measurement techniques, X-ray photoelectron spectroscopy, and auger electron spectroscopy. The results demonstrate that 3 wt% of nickel addition reduced the corrosion rate to 17 nA/cm 2 compared to 730 nA/cm 2 of carbon steel in the contaminated concrete condition. The enhancement of corrosion resistance for nickel-bearing steel was attributed to the formation of protective oxide film. The oxide film exhibited n-type semiconductivity in which oxygen vacancy was the main defect. The involvement of nickel in the formation process of oxide film changed its structure and composition. Nickel was enriched in the oxide film, simultaneously decreasing the defects density and the whole thickness of oxide film, and together with the increase of the Fe 2+ /Fe 3+ ratio and the inner barrier oxide film thickness. The protective inner barrier layer of oxide film on the nickel-bearing steel can strongly inhibited the corrosive attack.