Characteristics of the random transients caused by clustered pitting corrosion for Al-Mg microelectrode
Characteristics of the random transients caused by clustered pitting corrosion for Al-Mg microelectrode
复制标题
铝镁微电极簇状点蚀随机瞬变特性
DOI：
10.1002/maco.201911048
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发表时间：
2020
影响因子：
1.8
通讯作者：
Li Yu
中科院分区：
文献类型：
--
作者：
Guan Lei;Cai Jianmin;Li Yu
在3.5 wt%的曝气NaCl溶液（pH为3.5）中，使用两个名义上相同的Al-Mg微电极，通过电化学噪声测量研究了簇状点蚀过程。检测了与亚稳点蚀相关的电流瞬变，并用扫描电子显微镜观察了这些点蚀。结果表明，两类簇状凹坑可分别用电流瞬态表征。坑相互作用由一个多峰瞬态相互作用确定。考虑坑内析氢的非faradic电流和阴极电流，由单个单峰电流瞬态相关的综合电荷确定的平均体积小于实际坑的平均体积，而单峰瞬态计数大于SEM观察的平均体积。因此，这意味着发生了一个亚稳坑的再激活，而相关的毫秒瞬态表明，每次再激活只有一个与纳米It相关的单峰。这项工作的结果为利用电流瞬态的统计分析来预测相应的坑形态提供了见解。
The clustered pitting corrosion process has been investigated by electrochemical noise measurement using two nominally identical Al–Mg microelectrodes in aerated 3.5 wt% NaCl solution (pH 3.5). Current transients associated with the metastable pitting were detected and the pits were examined by scanning electron microscopy (SEM) observation. The results show that two types of clustered pits can be characterized by current transients separately. Pit interaction is confirmed by one transient with multiple peaks. Considering the nonFaradic current and cathodic current of H2evolution inside the pit, the average volume determined from an integrated charge associated with individual single peak current transient is lower than that of actual pits, while the single peak transient count is more than that from SEM observation. It thus implies that reactivation of one metastable pit occurs and the relevant millisecond transient demonstrates only a single peak associated with nanopit for each reactivation. The results from this work shed insight into the use of statistical analysis of current transients to forecast the corresponding pit morphology.