HAO Xiao-jun1, LEI Ying-chun2, HOU Hua1, ZHAO Yu-hong1, WANG Yi-du1
（1. School of Materials Science and Engineering, North University of China, Taiyuan 030051, China；2. Dept. of Environmental and Safety Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China）
Abstract： Electrochemical impendence spectroscopy (EIS) is applied to investigate the dissolution behavior of Al-Zn alloys in 3% NaCl solution at different polarization potentials. A new reaction model is proposed, and the activation mechanism of zinc in Al-Zn alloys is achieved. There are three intermediates in the dissolution process: Zn+ad, Zn2+ad and Al+ad, of which only Zn+ad can activate Al-Zn alloys. Most Zn+ad is produced by β-phase, and the alloys with 2.3%-3.8% (wt) Zn dissolve rapidly. The Al-Zn alloys of heart-shaped EIS are active in 3% NaCl solution, thus EIS characteristic can be used to distinguish the activation of Al-Zn alloys.
Key words： Al-Zn alloy sacrificial anode; reaction model; electrochemical impendence spectroscopy (EIS); activation mechanism; zinc enrichment phase (β-phase)
CLD number： TG174Document code： A
Article ID： 1674-8042（2017）02-0110-09 doi： 10.3969/j.issn.1674-8042-2017-02-002
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电化学阻抗谱研究Zn对用于阴极保护的Al-Zn合金在3% NaCl溶液中溶解行为的影响
郝小军1， 雷英春2， 侯华1， 赵宇宏1， 王一都1
（1. 中北大学 材料学院， 山西 太原 030051； 2. 太原工业学院 环境与安全工程系， 山西 太原 030008）
摘要:采用电化学阻抗谱（EIS）研究了Al-Zn合金在不同极化电位下， 3% NaCl溶液中的溶解行为， 提出了Al-Zn合金在该条件下的活化反应模型及机理。 该活化反应中产生3个中间产物： Zn+ad、 Zn2+ad和Al+ad， 其中只有Zn+ad可以活化Al-Zn合金。 大部分Zn+ad由β相反应产生， Zn含量2.3%-3.8%wt的Al-Zn合金可以快速溶解。 具有心形EIS的Al-Zn合金在该溶液中处于活化状态， 因此采用EIS可以区分Al-Zn合金的活化状态。
关键词:Al-Zn合金牺牲阳极； 反应模型； 电化学阻抗谱（EIS）； 活化机理； 富锌相（β相）
引用格式：HAO Xiao-jun, LEI Ying-chun, HOU Hua, et al. EIS studies the effect of Zinc to Al-Zn alloy used for cathodic protection in 3% NaCl solution. Journal of Measurement Science and Instrumentation, 2017, 8(2)： 110-118. ［doi： 10.3969／j.issn.1674-8042.2017-02-002］
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