Pit growth and stifling on carbon steel in CO2-containing media in the presence of HAc
Pit growth and stifling on carbon steel in CO2-containing media in the presence of HAc
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DOI：
10.1016/j.electacta.2009.07.061
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发表时间：
2009-12
影响因子：
6.6
通讯作者：
Jamel Amri;E. Gulbrandsen;Ricardo P Nogueira
中科院分区：
文献类型：
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作者：
Jamel Amri;E. Gulbrandsen;Ricardo P Nogueira
采用人工凹坑电极装置研究了碳钢管道在醋酸存在下的CO2腐蚀行为。利用零阻安培计(ZRA)监测了小攻角与外大表面之间的电势差和耦合电流。这一结果提供了强有力的补充证据，证明了在CO2腐蚀中，醋酸在局部腐蚀的增长机制中起着主要作用。窖池的繁殖和窒息似乎主要是通过分别对抗醋酸和二氧化碳的耗竭作用来实现的。研究还表明，纯欧姆液滴并不是扼杀管线顶端腐蚀等系统中局部腐蚀攻击的唯一因素。根据所获得的结果，对局部攻击的形态趋势提出了一个完整的情景，这与现场观测结果吻合得很好。
CO2corrosion of carbon steel pipelines in the presence of acetic acid was studied using artificial pit electrode assembly. The potential difference and the coupling current between the small attack and the outer large surface were monitored by means of a zero resistance ammeter (ZRA). The results give strong and complementary evidence about the major role of acetic acid in the growth mechanism of localized attacks in CO2corrosion. Pits seem to propagate and stifle mainly according to counteracting depletion effects of respectively acetic acid and CO2. It is also shown that the purely ohmic drop is not the only factor contributing to the stifling of localized corrosion attacks in systems like those of top of line corrosion. On the basis of the obtained results, a complete scenario was therefore proposed for the morphological trend of localized attacks, which is in good agreement with field observations.