Influence of AC Interference on the Corrosion Behavior of 2507 Super Duplex Stainless in Simulated Concrete Pore Solution

The corrosion behavior of 2507 super duplex stainless steel (SDSS) interfered by AC in simulated concrete pore solution containing Cl- was studied in this work. The results show that a rapid increase in i(p) and an apparent drop in E-p as well the significant decrease in R-f and R-ct values suggest that the addition of Cl- and applied AC result in an obviously harmful effect on the passive film, and enhance the dissolution rate of film. The change in ND and NA values indicates that the presence of Cl- or AC application reduce the compactness of film, increase the amount of defects, and weaken the protective ability. Especially at the combined action of Cl- and imposed AC, the instability of passive film becomes much worse, causing a further decrease in the anti-corrosion resistance of SDSS. AC facilitates the adsorption of Cl- and H+ ions on the defects within passive film.