| ZA27 alloys have excellent mechanical properties, foundry properties, machining properties and especial wearable properties. Furthermore, the raw material is low-cost and non-contaminated, and the source is wide. Due to all of these advantages, this kind of alloy has quickly grown up in domestic and overseas as new type of alloy. However, a main problem, aging invalidation due to intergranular corrosion, has limited the application of Zn-based alloys to a broader range for a long time. And the problem has not yet been resolved. Intended to solve the above problems, we focused our work on investigating the effects of alloy elements such as Cu, Mg, Si, Mn, Sb and Sn, and their content on the corrosion resistance of high Aluminum Zn-based ZA27 alloys. And the corrosion behavior of ZA27 alloys under simulation seawater circumstance was also studied.The work of the paper mainly consists of 3 parts and the corresponding results are listed as follow:(1) Corrosion behavior and mechanism of ZA27 alloys were investigated in 3. 5% NaCl aqueous solution. Taking the ZA27 alloy without adding alloy elements as reference, the effects of Cu, Mg, Si, Mn, Sb and Sn on the metallurgical structure and corrosion resistance of ZA27 alloy were investigated through examining the change of corrosion properties after an alloy element was added to the base alloy. In order to make a comprehensive compare on the corrosion resistance among the alloys with different component, both dynamic potential linear polarization and Tafel extrapolation were employed to measure the electrochemical parameters such as Ek, Rp, Icorr, ba and bc. It was shown that adding 3%Cu, 0. 06%Mg, 0.10%Si, 0. 75%Mn, 0. 2%Sb or 0. 1%Sn to ZA27 alloy will decrease its corrosion resistance.
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