Corrosion behavior of Cr/RE alloyed rebar in carbonated simulated concrete pore solutions with chloride ions

This study investigated the effect of the addition of Cr and RE microalloying regarding the steel rebar's resistance to corrosion in the co-existence of carbonation and chloride ions using electrochemical tests, scanning electron microscopy and confocal laser scanning microscopy. The best corrosion resistance of the Cr/RE microalloying rebar was found by the reduction in corrosion rates and the diminution of the rust layer. And during the initial stages of localized corrosion, the corrosion pits' depth was minimized, showing lateral expansion trends, which was supported by confocal laser scanning microscopy. Additionally, XPS analysis revealed that Cr/RE microalloying rebar can change the structure of the surface oxide film with a higher Fe(II)/Fe(III) ratio, which enhanced the surface oxide film's protective qualities.