充氢的X80高强钢在不同土壤中的电化学行为研究

摘要

基于极化曲线法和电化学阻抗谱法( EIS)研究充氢的X80高强钢在格尔木、大港站、大庆站、拉萨站4种模拟土壤溶液中的电化学行为。结果表明：不同充氢时间下的X80高强钢在4种模拟土壤溶液中的极化曲线均只表现出活化溶解状态，而未出现活化-钝化转变区，在一种土壤溶液中，其自腐蚀电位随充氢时间的延长逐渐下降，腐蚀电流密度增大，充氢促进了高强钢的腐蚀；在同一充氢时间下电荷转移电阻Rct在4种模拟土壤溶液中从拉萨站、大庆站、大港站到格尔木站依次减小。这4个站点土壤溶液耐腐蚀性能依次增强，与极化曲线中的分析结果一致。%The pipeline steel X80 after electrochemical hydrogen charging with different time in four simulated soil solutions ( Geermu, Dagang, Daqing and Lasa) was investigated using the polarization test and electrochemical impedance spectrosco-py ( EIS) measurement. Polarization test results show that high-strength steel X80 with different charging time presents simi-lar electrochemical behaviors, which is active in both the anode and the cathode. With the increase of charging time, the cor-rosion potential decreases and corrosion current density increases in the same simulated soil solution. The rank of charge transfer resistance from the lowest to the highest is Geermu, Dagang, Daqing and Lasa at the same hydrogen charging time. The maximum electrical conductivity of soil solution leads to the highest corrosion rate of X80 steel in Geermu simulated soil solution.