Electrochemical parameters of the high Al-Zn base alloy containing 30%

5

0% Al and 1.0%

2

.5% Cu

such as the Tafel parameters

resistance of linearization polarization （R

p

） and corrosion potential （E

k

）

have been measured by electrochemical measuring system in 3.5% NaCl solution. Corrosion morphology observation by the 3D video frequency microscope （HI-SCOPE Advanced KH-3000） was conducted also. The results show that the corrosion resistance of the alloy can be declined with increasing Al content and decreasing Cu content. The optimum corrosion resistance of the alloy can be observed with 30% Al content and 2.5% Cu content.