ISSN: 0149-6123
Page Count: 7

Some Laboratory Experiments on the Inhibitor Effect of Sodium Nitrite on Reinforcement Corrosion
Alonso, C
Researcher and research fellow, Institute of Construction and Cement “Eduardo Torroja,” CSIC,

Andrade, C
Researcher and research fellow, Institute of Construction and Cement “Eduardo Torroja,” CSIC,

González, JA
Senior researcher, National Centre of Mettallurgical Research, CSIC,

Abstract

The summary of several years of research about the inhibitor effect of NO2− on the corrosion of reinforcement is presented. Their inhibitor effect has been studied using galvanostatic and potentiodynamic polarization curves, and we have measured the corrosion rates using the polarization resistance method (linear polarization). Verification has been done by this last technique Rp, that the NO2− in concrete, if it is used in sufficient proportion, is a complete inhibitor when the Cl⁻ is added during the mixing (for example, mixing with seawater, calcium chloride (CaCl²) as an accelerator inhibitor). Insufficient amounts of NO2− have never provoked more corrosion in our experiments in concrete. The presence of NO2− always have produced a beneficial effect. The NO2− are also beneficial in carbonated concrete, suppressing or at least reducing the attacked area and the corrosion rate of the reinforcements.

Keywords:
reinforcement (structures), corrosion, inhibitors, sodium, nitrite, polarization resistance, concretes

Paper ID: CCA10064J
DOI: 10.1520/CCA10064J
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