低合金耐候钢在含氯离子环境中的耐腐蚀性能

Corrosion resistance of low alloying weathering steels in environment containing chloride ion

从钢基体和带锈层钢试样两方面研究了碳钢、Cor-Ten钢和贝氏体耐候钢在含氯离子环境中耐腐蚀性能。钢基体的极化曲线和电化学阻抗谱分析结果是贝氏体耐候钢具有最小腐蚀电流和最高极化电阻,表明细晶组织的贝氏体耐候钢基体耐蚀性能优于其它两种钢。X射线衍射分析结果是三种钢锈层的相组成是相近的,但带锈试样的电化学阻抗谱结果显示贝氏体耐候钢锈层的阻碍氯离子透过能力高于其它两种钢锈层。在整个加速腐蚀实验中贝氏体耐候钢失重始终最小,带锈层的贝氏体耐候钢的耐腐蚀性能也优于其它两种钢。

The corrosion resistance of carbon steel, Cor-Ten steel and bainitic weathering steel with and without rust layer in environment containing chloride ions was investigated. The polarization curve and electrochemical impedance spectrum of the steel matrix indicate that the bainitic weathering steel exhibits lowest corrosion current and highest polarization resistance, so the corrosion resistance of the fine crystalline bainitic weathering steel matrix is higher than that of the other two steels. The results of X-ray diffraction show that the rust phase constitution of the rust layer on the tested steels is similar. The electrochemical impedance spectrum of steel samples with rust layer indicates that the rust layer on the bainitic weathering steel has highest ability to block permeation of chloride ion. The mass loss of the bainitic weathering steel is the lowest in whole accelerated corrosion test, the corrosion resistance of the bainitic weathering steel with rust layer is also higher than that of the other two steels.