Corrosion behavior of pure zinc and its alloy under thin electrolyte layer

作     者：Liyun ZHENG Fahe CAO Wenjuan LIU Bingli JIA Jianqing ZHANG 

作者机构：Department of Chemistry Zhe.jiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2010年第23卷第6期

页      面：416-430页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by National Natural Science Foundation of China(Nos.50801056 and J0830413) the National R&D Infrastructure and Facility Development Program of China (No.2005DKA10400-Z20) the Zijin Project of Zhejiang University 

主　　题：Thin electrolyte layers EIS Cathodic polarization FTIR micro spectroscopy SEM 

摘      要：The corrosion behavior of zinc and its alloy under thin electrolyte layers （TEL） in 0.1M NaC1 solution was investigated by cathodic polarization curves and EIS. There was only one phase in pure zinc while zinc alloy consisted of eutectic phase and primary phase. Corrosion rate of zinc alloy was faster than that of pure zinc due to the effect of the micro-galvanic couples between the primary phase and the eutectic phase. The results indicated that corrosion rate of zinc alloy was greatly enhanced under TEL than that in bulk solution. Pure zinc exhibited minimum corrosion resistance as TEL decreased to 198 #m. Zinc and its alloy exhibited localized corrosion under TEL while it was more uniform in bulk solution. There were two capacitive loops in high frequency （HF） and middle frequency （MF） respectively, with finite length diffusion in low frequency （LF） presented in EIS. For pure zinc under TEL below 300 pm an additional inductive loop presented in MF-LF. The corrosion products and morphology were respectively examined by X-ray diffraction （XRD）, FTIR （Fourier Transform Infra Red） and SEM-EDS. FTIR micro spectroscopy results indicated that the component of the corrosion products was similar at different section of the specimen surface but different in content.