干湿循环条件下有机涂层/碳钢的电化学阻抗谱等效电路模型的建立与解析  

Establishment and Analysis of Equivalent Circuit Models of Electrochemical Impedance Spectroscopy of Organic Coating/Carbon Steel Electrode under Dry-Wet Cyclic Condition

作　　者：赵霞[1] 李伟华[1] 侯保荣[1] 王佳[2,3] 庞雪辉[1,4] 

机构地区：[1]中国科学院海洋研究所山东省腐蚀科学重点实验室,山东青岛266071 [2]中国海洋大学化学化工学院,山东青岛266100 [3]金属腐蚀与防护国家重点实验室,辽宁沈阳110016 [4]济南大学化学化工学院,山东济南250022

出　　处：《材料保护》2011年第3期20-23,89,共4页Materials Protection

基　　金：国家科技支撑计划(2007BAB27B03);国家863计划(2008AA09Z317)资助

摘　　要：研究干湿循环条件下有机涂层/金属电极的阻抗模型对于理解浪溅区钢铁设施的失效速率加快现象具有重要意义。在室内模拟干湿循环条件,采用电化学阻抗谱方法研究了30个干湿循环下醇酸铁红涂层/碳钢电极在3.5%NaC l溶液中的失效过程,建立了涂层失效在不同阶段的4种等效电路模型,解析了涂层电容及涂层电阻2个参数在30个循环周期内的变化规律。结果显示:涂层在浸泡阶段,电容逐渐增大,在干燥阶段,电容随着水分的蒸发而逐渐降低;涂层电阻在浸泡阶段逐渐降低,在干燥阶段逐渐增大。The deterioration process of iron oxide red alkyd primer/carbon steel electrode subjected to dry-wet cycles of 30 times in 3.5% NaCl solution was investigated by means of electrochemical impedance spectroscopy.Four models of equivalent circuit of coating deterioration at different stages were established,and the variation of the coating capacitance and resistance during the cycles was analyzed.It was found that the coating capacitance increased gradually at the immersing stage and decreased along with the evaporation of water at the drying stage,while the coating resistance decreased at the immersing stage and increased at the drying stage.

关 键 词：干湿循环 有机涂层/碳钢电极 电化学阻抗谱 等效电路 解析 

分 类 号：TG174.36[金属学及工艺—金属表面处理]