Evaluation of Corrosion and Erosion-Corrosion Behavior of X65 Pipeline Steel in Flowing CO₂-Saturated Electrolyte Available to Purchase

In this study, the corrosion and erosion-corrosion behaviors of X65 pipeline steel in the flowing CO₂-saturated electrolyte were electrochemically studied using a rotation disk system. The results showed that the accumulation of the Fe₃C layer in the electrolyte without sand particles enhanced the cathodic reaction, increasing the corrosion rate. The increase in flow velocity facilitated the rapid accumulation of a thick Fe₃C layer, which linearly increased the corrosion rate with increasing rotation speed. The sand impacts removed the corrosion product layer and broke the exposed Fe₃C network, resulting in a negative synergy of erosion-enhanced corrosion. The erosion-corrosion negatively affected ferrites compared with the pearlites in an electrolyte containing sand due to the weaker erosion resistance.