CORROSION MECHANISM OF CARBON STEEL IN CHLORIDE SOLUTION

An accelerated corrosion test of immersion-dry-wet combined cycles for carbon steel in 3%NaCl solution for 50h was performed.The corrosion products were analyzed by meas of IR,XRD and SEM.The corrosion products were composed of γ-FeOOH,α-FeOOH,Fe3O4 and a little β-FeOOH.The γ-FeOOH and α-FeOOH were formed due to the transformation from Ferrihydrite(Fe5HO8·4H2O) which dissolved by FeOH+.β-FeOOH and Fe3O4 were transformed from green rust.The α-FeOOH with course grains was transformed from β-FeOOH automatically.The products were related to high corrosion rate.