ABSTRACT

To examine the macro-galvanic corrosion of carbon steel near the air–liquid interface, a test panel of array electrodes was developed for investigating the corrosion behaviour in NaCl solution and wet soil environment. The corrosion rates were evaluated by electrochemical approaches and verified by the corrosion exposure tests. The analysis focused on the interaction between the macrocell and microcell according to the ZRA, EIS, and OCP measurements. Test results reveal that the coexisting of macrocell and microcell corrosion would change the position of maximum corrosion, and it was inferred the relationship of actual current density and microcell current density. In addition, the wet soil environment shows both microcell and macrocell corrosion near the air–liquid interface should be more severe than that in an iso-concentrated NaCl aq environment, whereas its macro-galvanic interaction of steel at the deep region should be smaller due to the low-diffusion rate in the soil environment.

摘要

为了检查气液界面附近碳钢的宏观电偶腐蚀，开发了阵列电极测试板，用于研究 NaCl 溶液和潮湿土壤环境中的腐蚀行为。通过电化学方法评估腐蚀速率并通过腐蚀暴露试验验证。根据 ZRA、EIS 和 OCP 测量，分析侧重于宏蜂窝和微蜂窝之间的相互作用。测试结果表明，宏电池和微电池腐蚀的共存会改变最大腐蚀的位置，从而推断出实际电流密度与微电池电流密度的关系。此外，