Hydrogen-enhanced corrosion behaviour of Cu-doping low-alloy steels through corrosion tests and first-principles calculations

Abstract

This study examines the crucial role played by Cu in electrochemical corrosion under marine and hydrogen-coupled environments. The adsorption energies of hydrogen and chlorine at different surface sites of α-Fe and Cu-doped α-Fe were analysed using first-principles computations. A significant increase in adsorption energies introduced by Cu was discovered and evidenced by shifts in electrochemical polarisation curves, corresponding with the corrosion morphologies. Moreover, we delve into the effects of Cu on hydrogen solubility and diffusion within the steel, showing that Cu atoms affect hydrogen transport by altering the energy barriers and forming precipitates. These comprehensive insights provide a deeper understanding of the role of Cu doping in enhancing the performance and durability of Ni-containing steels in corrosive and hydrogen-prone environments, offering valuable guidelines for material design and application in industrial settings.