通过高温高压试验和电化学技术研究了温度对L80碳钢在含CO₂天然海水中腐蚀行为的影响,并用扫描电子显微镜(SEM)、能量弥散X射线谱(EDS)和X射线衍射(XRD)对腐蚀产物膜进行了表征。结果表明,随着温度的升高,L80碳钢在液相条件下的腐蚀速率呈先增大后减小的趋势,在90℃达到最大值;而在气相条件下呈现与液相条件下完全相反的趋势。腐蚀产物膜的主要成分为FeCO₃,FeCO₃膜层的阴离子选择透过性以及Cl^-在L80碳钢表面的吸附促进了CO₂腐蚀,在90℃的气相和液相中所形成的腐蚀产物膜的电化学特征进一步验证了高温高压试验结果。

The test of high temperature and high pressure and electrochemical technology were utilized to investigate the effects of temperature on the corrosion behavior of L80 carbon steel in CO₂ containing natural seawater. The Scanning Electron Microscope (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), and X-Ray Diffraction (XRD) were used to characterize corrosion scale. The results show that firstly, corrosion rate of L80 carbon steel increases and then decreases with increasing temperature in the liquid phase, and the maximum value lies at 90℃, while this variation trend is completely opposite to that in the gaseous phase, a corrosion product layer is mainly composed of FeCO₃, anion selective permeability of FeCO₃ product film and the absorption of Cl^- on steel surface prompt the CO₂ corrosion on the L80 carbon steel surface, the electrochemical properties of corrosion scale formed at 90℃ in liquid and gaseous phases further prove the test results described above.