目的 对 X80 管线钢表面进行离子渗氮处理,研究其渗氮层在库尔勒土壤模拟溶液中浸泡 30,60,90 d 的腐蚀性能及规律。 方法 通过动电位极化和交流阻抗谱分析 X80 管线钢渗氮层对腐蚀性能的影响,采用 SEM,XRD 和 EDS 技术对腐蚀产物膜的表面形貌和组成成分进行分析测试。 结果 随着腐蚀时间的增加,渗氮 X80 钢的自腐蚀电流密度减小到 1. 33 μA/ cm2,自腐蚀电位增加至-225 mV,腐蚀速率显著减小;腐蚀产物主要为 Fe2O3,FeO(OH),Fe(OH)3 和 Fe3O4。 结论 浸泡相同时间,离子渗氮试样的自腐蚀电位更正,自腐蚀电流密度降低 1 个数量级,电荷转移电阻增大 2 个数量级,比原始 X80 管线钢更耐蚀。

Objective The surface of commercial X80 pipeline steel was modified using plasma nitriding, to study the corrosion resistance and rule of plasma nitriding X80 steel immersed in Ku’erle soil simulation solution for 30 days, 60 days, and 90 days. Methods The effect of the nitrided layer on the corrosion resistance of X80 steel was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurement, The morphology and composition of the corrosion products were investigated using SEM, XRD, and EDS. Results The results showed that: with the increasing corrosion time, the corrosion current density of nitrided X80 steel decreased to 1. 33 μA/ cm2, the corrosion potential increased to -225 mV, and the corrosion rate was significantly reduced; the corrosion products were mainly composed of Fe2O3, FeO (OH), Fe(OH)3 and Fe3O4. Conclusion As compared with the X80 steel, after immersion for the same time, the specimen treated by plasma nitriding had a more positive corrosion potential, the corrosion current density was decreased by one order of magnitude, the charge transfer resistance was increased by two orders of magnitude, and the corrosion resistance was higher.