Corrosion Behavior of L245N Standard Steel in CO2 Saturated Brine under Flow Condition

Metals

Ying Hu¹  Yonghao Lu¹  Long Xin²  Tingguang Liu² 

[1] Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing 100083, China;National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing 100083, China;

关键词: flow condition;    L245N standard steel;    high salinity;    cementite;   

DOI  :  10.3390/met11060880

来源: DOAJ

【 摘 要 】

The corrosion behavior of oilfield used L245N standard steel was tested in simulated oilfield solution by dynamic high-temperature autoclave. The corrosion products were characterized by using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Electrochemical impedance spectroscopy (EIS) respectively. In addition, the corrosion rates and surface morphological characteristics of the steels after different exposure times were studied. The results showed that the corrosion rate decreased sharply and then increased with time in the high salinity flow solution, which was related to the formation of corrosion scale and the remaining cementite within it. At the beginning of the exposure time, the formed corrosion scale became thicker, resulting in a significant decrease of the corrosion rate. While with increasing time, on the one hand, the increased remaining cementite within corrosion scale facilitated the corrosion by the galvanic corrosion between the remaining cementite and the ferrite within the metal. On the other hand, the protective effect of corrosion scale formed on the remaining cementite skeleton declined due to the formation of large amounts of Fe_xCa_1−xCO₃, which also promoted the corrosion rate of the steels, both these ways contributed to a slow increase of corrosion rate.

【 授权许可】

Unknown