2018 Volume 58 Issue 5 Pages 936-942
The corrosion resistance of Cr bearing steel (CR) in concrete was estimated by the exposure test in a coastal environment. Carbon steel (SM) had a significant corrosion on the surface, and the concrete block had large cracks. On the other hand, CR had little corrosion, and there was no crack on the concrete. In the case of Electrochemical Impedance Spectroscopy (EIS) measurements, the impedance at low frequency region (ZL) of CR showed much higher values than that of SM. Cr and Si were enriched in inner rust of CR observed by Energy Dispersive Spectroscopy (EDS) measurement. Transmission Electron Microscopy (TEM) showed that nano complex iron oxides containing Cr and Si were formed in inner rust, which suppressed the corrosion of CR in the concrete.
