Corrosion Behavior of Enamel Coated Steel Rebar by EIS

Abstract:

In this study, the corrosion process of enamel-coated deformed rebar completely immersed in 3.5 wt.% NaCl solution was evaluated over a period of 84 days by EIS testing. Three types of enamel coating were investigated: pure enamel, 50/50 enamel coating, and double enamel. Surface condition of the enamel coatings that were intentionally damaged prior to corrosion tests was visually examined at different immersion times. After 84 days of testing, the damaged coating areas were characterized by SEM, and the corrosion products on and adjacent to the damaged areas were collected and analyzed by XRD. Corrosion initiated at the damaged locations with no undercutting of the coating observed. The 50/50 enamel coating had the least corrosion resistance, due to its interconnected pore structure, and prior damage drastically reduced the corrosion resistance of pure and double enamel coated rebar.

• Periodical: Advanced Materials Research (Volumes 450-451)
• Pages: 445-453
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.450-451.445
• Online since: January 2012
• Authors: Fu Jian Tang, Gen Da Chen, Jeffery S. Volz, Richard K. Brow, Michael Koenigstein
• Keywords: Corrosion Resistance, EIS, Enamel Coating, SEM-EDS, X-Ray Diffraction (XRD)

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