采用动电位极化和交流阻抗技术研究在库尔勒土壤模拟溶液中SO42-质量分数对X80管线钢腐蚀行为的影响,并利用金相显微镜观察不同SO42-质量分数下的腐蚀形貌.结果表明:X80管线钢在SO42-不同质量分数的库尔勒土壤模拟溶液中,其极化曲线呈现典型的活化溶解特征；随着SO42-质量分数的增加,X80钢的腐蚀速率呈现先增大、后减小的趋势；当SO42-质量分数为5％时,极化电阻Rp出现临界值,此时X80管线钢的腐蚀最严重;当SO42-质量分数为10％时,金属腐蚀反应严重受阻,其表面腐蚀现象不明显,只有几个小的腐蚀坑存在;溶液中的Cl-吸附在X80钢表面会导致金属发生腐蚀自催化过程；而SO42-优先于Cl-吸附在金属表面上,能够抑制Cl-对X80管线钢的腐蚀行为.%The effects of SO42- on corrosion behavior of X80 pipeline steel in simulated Ku'erle soil solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The corrosion morphologies were observed by metalloscope with different SO42- mass fractions. The results show that the polarization curves of X80 pipeline steel have typical characteristics of active dissolution in Ku'erle soil simulated solution. The corrosion rate of X80 steel first increases and then decrease with the increase of SO42- mass fraction. When the mass fraction of SO42- is 5%, there is a critical value on polarization resistance, and the corrosion behavior of X80 steel is the most serious at this time. When the mass fraction is 10%, there are only a few small corrosion pits on the surface of metal. The Cl- in the solution which is adsorbed on the surface of X80 steel can lead to metal corrosion autocatalytic process. The adsorption ability of SO42- is stronger than C1-, and so it is able to inhibit the corrosion behavior of X80 steel aroused from Cl- .
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