Influence of Temperature on CO2 Corrosion of Fe-0.21C-25Mn-5Cr-2Al-2Ni TWIP Steel

The corrosion and corrosion mechanism at different temperatures of TWIP steel(Fe-0.21C-25Mn-5Cr-2Al-2Ni) were studied by calculating the corrosion rates at different temperatures, observing the corrosion product morphology of SEM, analyzing the elements and components of corrosion products with EDS and XPS, when the pressure of CO2 was 2 MPa. It was found that the corrosion rate increased first and then decreased with temperature rising. The corrosion product film which had a small area of pitting and contained Cr materials mostly was very thin and uniform as a whole when temperature was 60 ℃. The product film was sheet and loosely arranged and uniform, and was mainly composed of hydroxide of Cr and Al when the temperature reached 90 ℃. The product film which had traces of crystal growth was rectangular granular and close stacking and uniform when the temperature reaches 120 ℃, and it was carbonates of Fe and Mn.