中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 13 No. 2 April 2003 |
impedance spectroscopy
（1. Department of Chemistry, Zhejiang University,
Hangzhou 310027, China;
2. State Key Laboratory for Corrosion and Protection,
Institute of Metal Research, Chinese Academy of Sciences,
Shenyang 110016, China）
Abstract:The exfoliation morphologies and electrochemical impedance spectroscopy (EIS) features of as-received rolled AA8090 Al-Li alloy in EXCO solution were studied. The EIS was simulated using an equivalent circuit. The results show that once the exfoliation occurs, the EIS is composed of two capacitive arcs at high frequency and mediate-low frequency; among them, the capacitance corresponding to high frequency (C1) is originated from original flat alloy surface, while the capacitance corresponding to mediate-low frequency (C2) from new interface exposed to EXCO solution due to the exfoliation and the ratio of C2 to C1 increases with exfoliation degree. It is advanced that the exfoliation degree can be quantitatively judged through this ratio.
Key words: rolled AA8090 Al-Li alloy; exfoliation degree; electrochemical impedance spectroscopy (EIS)
