Effect of exposure angle on the corrosion behavior of X70 steel under supercritical CO2 and gaseous CO2 environments

The corrosion behavior of X70 steel with different exposure angles under supercritical CO2 and gaseous CO2 environments were studied. The results showed that the diffusion of the corrosive species in the water droplets in supercritical CO2 phase was more significant than that in aqueous phase, which accelerated the cathodic reactions. The corrosion rate in supercritical CO2 phase was much higher than that in gaseous CO2 phase due to the higher mutual solubility (g/L) of H2O and CO2 in supercritical CO2 phase. Exposure angle significantly affected the corrosion behavior of the steel in supercritical CO2 phase.