Al－Mg合金在不同pH值的NaCl溶液中的腐蚀行为

CORROSION BEHAVIOUR OF Al-Mg ALLOYS IN NaCl SOLUTIONS WITH VARIATION OF pH

用电化学阻抗谱（ＥＩＳ）技术研究了ＬＦ３Ｍ和ＬＦ１１Ｍ两种Ａｌ－Ｍｇ合金在不同ｐＨ值的２７％ＮａＣｌ溶液中的腐蚀行为结果表明，Ａｌ－Ｍｇ合金在不同ｐＨ值的ＮａＣｌ溶液中不同极化电位Ｆ处于不同的腐蚀状态。

In this paper, the electrochemical impedance spectroscopy (EIS) is employed to investigate the corrosion performance of two Al-Mg alloys (LF3M and LF11M) in 2.7% NaCl solutions with variation of PH. The results reveal that various corrosion states will appear when the two Al-Mg alloys are in the media containing Cl--with different PH, which corrospond to the defined features in the EIS plots. Especially, if the PH value is less than 4, no stable passive films on the surface of both of the alloys exsist, the active dissolution occures and the corrosion is accelerated. In addition, the reason is also discussed for the higher sensitivity to localized corrosion of the two Al-Mg alloys in the Xiamen sea environment.