Ensayos de laboratorio sobre el efecto inhibidor de los NO2- sobre la corrosión de las armaduras

Abstract

We present the summary of several years of research about the inhibitor effect of NO₂^- on the corrosion of reinforcements. We have studied their inhibitor effect using galvanostatic and potentiodynamic polarization curves and we have measured the corrosion rates using the Polarization Resistance method (linear polarization). We have verified by this last technique, Rp, that the NO₂^- in concrete, if they are used in sufficient proportion, are a complete inhibitor when the Cl are added during the mixing (e.g. mixing whith sea water, CaCl₂ as an accelerator in inbitor). Inssufficient 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.