Utilizzo di nitrati come inibitori di corrosione per le armature nel calcestruzzo

Corrosion inhibitors have been long considered as an effective preventative technique to slow down the onset and/or propagation of corrosion phenomena in reinforced concrete. Several substances have been evaluated as possible candidates, and great interest has been dedicated to nitrite ion. When investigating how these substances slow down corrosion related processes – chlorides diffusion, critical chloride threshold, CO2 penetration and corrosion propagation –interactions between inhibitor and concrete are also vital. Recently, nitrate based compounds have been proposed as corrosion inhibitors, as they present lower cost than nitrites and are already used in concrete as set accelerators. Some studies have shown that nitrates inhibiting mechanism is similar to that of nitrites. This work proposes the evaluation of a nitrate based substance as possible corrosion inhibitor in concrete, and compares its performance with a nitrite based inhibitor.