摘要
利用极化曲线、线性极化和电化学阻抗谱(EIS)研究了Q235钢在20～70℃、含水20%的大港土中的腐蚀行为.实验表明:Q235钢的腐蚀电流密度随温度升高而增大,线性极化电阻Rp及电荷转移电阻Rt随温度升高而减小;在阳极极化100～200 mV区间,Q235钢的电极过程受到了一定阻滞,E～lgI曲线在该极化区间内的斜率随温度升高而呈指数衰减;利用腐蚀电流密度和线性极化电阻所计算的Stern公式中的B值要大于活性区均匀腐蚀所对应的B值,在实验温度范围内,其数值基本维持在44.2 mV左右;线性极化电阻Rp是整个电极反应过程的综合体现,在含水20%的大港土中,由于受扩散过程控制,Rp的数值要比电荷转移电阻Rt大得多.
The corrosion behavior of Q235 steel in Dagang soil with a 20 % water content at different temperatures was studied by the means of polarization curve, linear polarization and electrochemical impedance spectroscopy （EIS）. The results indicate that at the range of 20 to 70 ℃, with increasing temperature the corrosion current density Icorr increases, and the linear polarization resistance Rp and the charge transfer resistance Rt depress. At the range of 100 to 200 mV of anodic polarization, the electrode reaction of Q235 steel is blocked, and the slops of E to lgI curves exponentially decrease with increasing temperature. The value of B which is calculated by the corrosion current density Icorr and the linear polarization resistance Rp is bigger than the one which accounts for active uniformity corrosion, and keeps constant at about 44.2 mV. Due to the control of diffusion process, the linear polarization resistances Rp is much bigger than the charge transfer resistance R t obtained from equivalent circuit simulation of EIS technology.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2009年第1期48-53,共6页
Journal of University of Science and Technology Beijing
基金
科技部国家科学基础条件平台建设项目(No.2005DKA10400)
国家科技支撑计划资助项目(No.2006BAK02B01-06)
关键词
Q235钢
温度
极化曲线
电化学阻抗谱
线性极化电阻
0.235 steel
temperature
polarization curve
electrochemical impedance spectroscopy
linear polarization resistance
