中文摘要：

采用电化学阻抗谱（EIS）和阴极极化曲线研究了Q235钢在薄液膜条件下的大气腐蚀过程,探讨了液膜厚度、Cl-和腐蚀产物对Q235钢失效过程的影响。结果表明液膜厚度会影响O2的扩散过程,并进一步影响腐蚀速率;Cl-环境下,Q235钢腐蚀产物分成2层,外层为多孔疏松层,内层主要为α-FeOOH和γ-FeOOH组成的锈层,同时本体溶液中腐蚀产物仅为1层且疏松;薄液膜下腐蚀速率较本体溶液明显增加,当液膜厚度为202μm时,在阴极过程和腐蚀产物的共同控制下,腐蚀速率最大,局部腐蚀孔最深。

英文摘要：

The atmospheric corrosion process of Q235 steel under thin electrolyte layer（TEL） was investigated by electrochemical impedance spectroscopy（EIS） and cathodic polarization.The influence of the thickness of TEL,chloride ions,and corrosion production on the degradation process of Q235 steel was discussed.The results indicated that the thickness of TEL affect the diffusion process of O2,which further influence the corrosion rate.The effect of TEL to the two-layer rust under Cl-containing environment was analyzed.The rust layer is composed of outer layer which is porous and loose and an inner layer containing α-FeOOH and γ-FeOOH.However the rust layer was only one layer in bulk solution which was rather porous.The corrosion rate of Q235 steel under TEL is higher than that in bulk solution,which is controlled by cathodic process and corrosion product.The corrosion rate is maximum under 202 μm TEL,while localized pit is deepest.