Application of a Quasi In Situ Experimental Approach to Estimate 3-D Pitting Corrosion Kinetics in Stainless Steel
Application of a Quasi In Situ Experimental Approach to Estimate 3-D Pitting Corrosion Kinetics in Stainless Steel
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DOI：
10.1149/2.0381613jes
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发表时间：
2016-01-01
影响因子：
3.9
通讯作者：
Engelberg, D. L.
中科院分区：
文献类型：
--
作者：
Almuaili, F. A.;McDonald, S. A.;Engelberg, D. L.
采用准原位x射线计算机断层扫描（x射线CT）方法获得了304L型不锈钢的点蚀动力学。构建了一种微型电化学电池，用于在氯化物溶液中对电线试样进行动态电位极化成像。观察到三个离散坑的形成，允许比较真实坑的几何形状和不同的几何假设来估计坑的生长动力学。x射线CT计算的凹坑体积与法拉第定律计算的金属溶解体积吻合较好。在坑形核阶段观察到平均电流密度的大波动，随后是坑生长，平均电流密度为1(-3)A. cm（-2）。与这些凹坑相关的稳定性产物约为0.3-0.6 a.m(-1)，扩散系数（d三角形C）为1.68-3.04 × 10-8 mol. cm-1。(1)。扩散系数为0.83-0.96 × 10(-5) cm(2)。s（-1）估计金属离子浓度为4.2 M. (C)作者(s) 2016。由ECS出版。这是一篇基于知识共享署名4.0许可（CC BY, http://creativecommons）的开放获取文章。Org/licenses/by/4.0/)，允许在任何媒介上不受限制地重复使用该作品，只要正确引用原始作品。
Pitting corrosion kinetics of type 304L stainless steel have been obtained using a quasi in-situ X-ray computed tomography (X-ray CT) approach. A miniature electro-chemical cell was constructed to allow imaging during potentio-dynamic polarization of a wire specimen in chloride solution. The formation of three discrete pits was observed, allowing comparison between real pit geometry and different geometrical assumptions to estimate pit growth kinetics. The pit volumes obtained by X-ray CT showed a good fit with the volume of metal dissolution calculated using Faraday's law. Large fluctuations of the mean current density were observed during the pit nucleation stage, followed by pit growth with mean current densities of 1(-3) A. cm(-2). Stability products associated with these pits were on the order of 0.3-0.6 A. m(-1), with a diffusivity parameter (D. triangle C) of 1.68-3.04 x 10-8 mol. cm-1. s(-1). Diffusion coefficients for stable pit growth of 0.83-0.96 x 10(-5) cm(2). s(-1) were estimated for metal ion concentrations of 4.2 M. (C) The Author(s) 2016. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons. org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited.