Corrosion rate of galvanized steel immersed in saturated solutions of Ca(OH)2 in the pH Range 12-13.8

Abstract

The influence of the alkaline content of cement on the corrosion kinetics of galvanized reinforcements has been studied, by means of the polarisation resistance method, in saturated solutions of $Ca(OH)_{2}$ with additions of NaOH, KOH and $SO^{2}4$, thus simulating the liquid phase of concrete. It has been established that below a threshold pH the coating protects the surface; above this pH the coating is attacked, disappearing in a few days. Cements with low alkali contents and proper concrete dosage must therefore be used to ensure that the pH remains below the threshold value.