Abstract: The corrosion behavior of auxiliary anode under the combined action of alternating current density and cathodic protection were studied. Firstly, the corrosion rate and corrosion image were analyzed by immersion experiment, and the corrosion process was determined. Secondly, the electrochemical behaviors of the auxiliary anode under different conditions were analyzed by electrochemical test, and the corrosion behaviors of the auxiliary anode under different conditions were characterized according to the change of its corrosion kinetic parameters. The results show that the corrosion product layer formed under lower alternating current density overlays on the surface to slow down the corrosion, while the higher alternating current density can break down the corrosion product layer to activate the corrosion reaction. The cathodic protection current causes the corrosion product layer to be in the constant destruction and the generation process, further promotes the corrosion reaction. The results of immersion experiment are in good agreement with those of electrochemical test.

Key words: AC interference, Cathodic protection, Auxiliary anode, Corrosion, Electrochemical test

摘要： 研究了交流电流密度和阴极保护共同作用下的辅助阳极腐蚀行为。首先，通过浸泡实验分析了阴保和交流电流密度单独和共同作用时的腐蚀速率和腐蚀图像，确定了其腐蚀过程；其次，通过电化学测试分析了不同条件下辅助阳极的电化学行为，并根据其腐蚀动力学参数的变化表征了不同条件下辅助阳极的腐蚀行为。结果表明，较小交流电流密度下形成的腐蚀产物层覆盖在辅助阳极表面减缓了腐蚀的发生，而较大交流电流密度能够击穿腐蚀产物层活化腐蚀反应；阴保电流从内部使腐蚀产物层处于不断的破坏和生成过程中，进一步促进腐蚀反应的发生；浸泡实验结果与电化学测试结果呈现较好的一致性。

关键词: 交流干扰, 　阴极保护, 　辅助阳极, 　腐蚀, 　电化学测试