Authors: M.V. Diamanti, M. Ormellese, E.A. Perez-Rosales, MP. Pedeferri, G. Raffaini, F. Ganazzoli
Affilation: Politecnico di Milano, Italy
Pages: 689 - 692
Keywords: passive films, inhibition mechanism, localized corrosion
Corrosion inhibitors are one of the preventative techniques used to prevent chloride-induced corrosion in reinforced concrete structures. Several commercial inhibitors are available on the market, but their efficiency as well as their inhibitive mechanism are not well understood. In this paper the inhibiting behaviour of five nano-sized organic substances in delaying chloride-induced corrosion was evaluated in alkaline solution using electrochemical impedance spectroscopy and potentiodynamic tests. Experimental and theoretical results confirmed both the presence of a strong physisorption between the inhibitors and the substrate, and of repulsive interactions between the molecules of inhibitors, leading to the formation of a non-homogenous monolayer, i.e. a nanometric layer of inhibitor molecules scattered across the surface.