氯离子对钝态金属电极阻抗频谱的影响

中国腐蚀与防护学报

1989, Vol. 9

Issue (4): 261-270

研究报告

本期目录 | 过刊浏览

氯离子对钝态金属电极阻抗频谱的影响

曹楚南;王佳;林海潮

中国科学院金属腐蚀与防护研究所;中国科学院金属腐蚀与防护研究所;中国科学院金属腐蚀与防护研究所

EFFECT OF Cl~- ION ON THE IMPEDANCE OF PASSIVE-FILM-COVERED ELECTRODES

Cao Chunan Wang Jia and Lin Haichao (Institute of Corrosion and Protection of Metals; Academia Sinica)

全文: PDF(879 KB)

摘要: 研究了钝化的20号碳钢电极在受到溶液中的CI~-的作用而尚未生成腐蚀孔时(孔蚀诱导期内)的阻抗频谱特征。发现极化电阻比之没有Cl~-时降低了4个数量级,而且低频区阻抗实部呈现电感性收缩现象。这种实部收缩现象随着时间的增加逐渐减弱。对于表面复盖有钝化膜的金属电极的交流阻抗提出了一个统一的数学模型,可以解释溶液中没有Cl~-时和受到Cl~-影响时的钝态金属电极的阻抗频谱。

Abstract：The effect of Cl~- ion on the features of impedance of mild steel and iron electrodes with passive film on their surfaces is studied.In NaNO_2 solution, the polarization resistance and time constant of mild steel electrode are estimated to be 6.35 megohm/cm~2 and 87.5 sec respectively, which are very close to the published data for iron in borax-boric acid solution.As Cl~- ion is introduced into various passivators solutions, the polarization resistance and time constant of the passive-film-covered mild steel and iron electrodes reduce by ca.4 orders of magnitude during pit incubation period,i.e., before the passive film is perforated.In addition, an inductive component is observed on impedance plane in low frequency range for all systems studied.This inductive component is fading away with time gradually.However, even if the inductive are disappears at last, the shrinkage of the real part of the impedance at very low frequencies can still be observed before pits initiate.An equation describing the impedance of passive-film-covered electrodes is proposed, based on which, three cases of the impedance diagrams of passive-film-covered electrodes can be demonstrated.If R_f, which denotes the resistance for the passive-film-forming current density passing through the passive film, is approximately equal to R_s, which denotes the resistance for the passive film dissolution process, a single capacitive arc on the impedance diagram is obtained and the estimated polarization resistance R_p equals R_f, whose magnitude is abont 6 megohm·cm~2 as usually observed for passive electrodes.When R_s>R_f, the faradaic impedance is equivalent to a serial connection of a resistance and a capacitance as observed for valve metals electrodes.If R_s

收稿日期: 1989-08-25

基金资助:科学院院内科学基金课题

	服务

	把本文推荐给朋友
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	曹楚南
	王佳
	林海潮
44.8K

引用本文:

曹楚南;王佳;林海潮. 氯离子对钝态金属电极阻抗频谱的影响[J]. 中国腐蚀与防护学报, 1989, 9(4): 261-270.
. EFFECT OF Cl~- ION ON THE IMPEDANCE OF PASSIVE-FILM-COVERED ELECTRODES. J Chin Soc Corr Pro, 1989, 9(4): 261-270.

链接本文:

https://www.jcscp.org/CN/ 或 https://www.jcscp.org/CN/Y1989/V9/I4/261

[1] Epelboin,I.,Gabrielli,C.,Keddam,M.and Takenouti,H,; ASTM Sympo-sium on ElectrochemicaI Techniques in Corrosion Science; p.150(1979)
[2] Mansfeld,F.and Kendig,M.W.; Paper No.255 CORROSION/83, Calif.;(1983)
[3] Epelboin, I., Gabrielli, C., Keddam, M. and Takenouti, H.; Comprehensive Treaties of Electrochemistry, Ed. Bockris, J. O'M, Conway, B.E.and Yeager,E.B.; 4,151～192(1981)
[4] Shire Haruyama and Toots Tsuru; Passivity of Metals, Ed.Frankenthal, R.P., Kruger, J., P.564,The Electrochemistry Society, Princeton(1978)
[5] Bertocci, U.J.;Electochem.Soc.,127,1931(1980)
[6] Ferreira, M.G.S. and Dawson, J.L.; Corrosion Science, 26, 1009(1986)
[7] 王佳,施存余,宋诗哲,曹楚南;中国腐蚀与防护学报,9(1) ,11(1989)
[8] Chao, C.Y., Lin, L.F. and Macdonald, D.D.;J.Electrochem. Soc., 128, 1187(1981) ;1197(1981)
[9] Urquidi, M. and Macdonald, D.D.; J.Electrochem. Soc., 132, 555(1985)
[10] Vetter, K.J.; Electrochim. Acta, 16, 1923(1971)
[11] 安住久和,大(土冢)俊明,佐藤教男;日本金属学会志,49,729(1985)
[12] Macdonald, D.D.; Trausient Techniques in Electrochemistry, pp.299～303,Plenum Press, New York(1977)
[13] Okada, I.; Corrosion Science, 26, 839(1986)

No related articles found!

Viewed

Full text

Abstract

Cited

Shared

Discussed