周浸加速循环腐蚀试验中耐候钢锈层的电化学特征

The Electrochemical Characteristics of Rust Layer Formed on the Weathering Steel in Cyclic Dry/Wet Laboratory Test

通过周浸加速腐蚀试验研究了耐候钢和碳钢在 3 5 %NaCl溶液中的腐蚀情况。试验结果表明 :腐蚀 2 0 0h的耐候钢表面生成的致密锈层主要由α CrxFe1-xOOH组成。通过人工合成相应组分的腐蚀产物 ,并测试其离子选择性 ,发现该锈层有阳离子选择特性 ,能阻挡氯离子进入 ,降低钢的大气腐蚀速率 ;电化学交流阻抗 (EIS)

The corrosion process of both carbon steel and weathering steel was analyzed through cyclic dry/wet accelerated laboratory tests in 3 5% NaCl solution The results indicated that a compact rust layer had been formed on weathering steel tested for about 200 hours The layer is composed mainly of Cr xFe 1-x OOH phase, which is equipped with cation selecting ability and can resist the entrance of chloride ion, therefore weathering steel has higher anticorrosion ability than carbon steel Furthermore, the result of EIS analysis indicates that the corrosion process of weathering steel is controlled by diffusion