A time-resolved study of PbCl2-induced corrosion of low-alloyed steel in the presence of water vapour at 400 °C

Journal article, 2024

A laboratory study of a low-alloyed steel (T22) exposed to an 5% O2 + 20% H2O + N2 bal. gas in the presence of PbCl2(s) and PbO(s) at 400 °C is presented. The presence of PbCl2(s) strongly accelerates corrosion by promoting oxide delamination and crack formation. The corrosion attack is explained according to an electrochemical mechanism, involving the inward diffusion of chlorine ions and formation of metal chlorides at the metal/oxide interface. The role of Cl in PbCl2-indcued corrosion of low-alloyed steels is argued to be the major driving force while the role of Pb in the corrosion attack is minor.