The corrosion behavior of ZA27 alloys in 35 g/L NaCl solution has been examined by electrochemical and immersion corrosion tests. The effects of Cu and Sb on the Tafel curves and electrochemical parameters

including free corrosion potential

electric resistance of linear polarization

corrosion current

of the ZA27 alloy have been investigated. The surface morphology of the alloy after corrosion treatment has been observed by SEM （scanning electron microscope） and EDAX. The results indicate that low Cu content can improve the corrosion resistance of the ZA27 alloy

which is attributed to Cu making the free corrosion potentials shift to positive to decrease the corrosion current density

however

excessive Cu content can deteriorate the corrosion resistance. The free potential of the tested alloy shifts to negative to increase the corrosion current density with the increase of Sb

declining the corrosion resistance of the ZA27 alloy.