Corrosion behavior of low-alloy steel containing 1% chromium in CO2 environments

Corrosion behavior of low-alloy steel containing 1% Cr (1Cr) with normalized (ferritic-pearlitic) and quenched-and-tempered (tempered martensitic) microstructures was investigated in CO2 environments at 60 °C. The severe localized corrosion which was observed in N80 carbon steel, did not exist for 1Cr steel due to the formation of a compact and self-repairable Cr-rich scale. For 1Cr steel, the corrosion resistance with ferritic-pearlitic microstructure was better than that with tempered martensitic microstructure. An apparent corrosion scale spallation was observed on the surface of quenched-and-tempered 1Cr steel, while only slight scale spallation was seen for normalized 1Cr steel.