Characteristics of Corrosion Scales on Steels in a CO2-Saturated NaCl Brine

Abstract

A consequence of corrosion of steel in the presence of oxygen-free carbon dioxide and a water phase is the formation of an iron carbonate (FeCO3) corrosion scale. This scale provides some protection of the steel from further corrosion. The protectiveness of the scale depends on environmental factors and characteristics of the steel. Information presented here describes structural characteristics of iron carbonate scales and discusses how structure may affect the corrosion mechanism. Examinations of iron carbonate scales revealed two kinds of scales and variations in scale thickness depending on the steel microstructure.