Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1469760 | Corrosion Science | 2011 | 10 Pages |
Measurements of corrosion rate of reinforcing steels have been carried out in solutions simulating electrolytic chloride environments in corrosion pits in the propagation period with sodium nitrite. A significant corrosion inhibition has been observed at relatively low chloride contents of 0.045 M due to the presence of nitrite in these systems, but its efficiency decreases when the pH is reduced. The corrosion intensity seems to be related to the [Cl−]/[OH−] ratio. Three different pH regions from acid to alkaline have been observed in terms of corrosion activity. An explanation on the behaviour of nitrite at different pH is given.
► NaNO2 was tested as steel corrosion inhibitor in solutions with different pH. ► Initial stage of propagation period was simulated by Ca(OH)2 and FeCl2 solutions. ► A NaNO2 concentration of 0.1 M shows better performance than 0.5 M. ► A NaNO2 concentration of 0.5 M can even increase corrosion rate of steel.