Effects of Si and Sn on Corrosion Resistance of ZA27 Alloy

The Tafel curves and electrochemical parameters such as free corrosion potential,resistance of linear polarization,corrosion current density of ZA27 alloys which contains 0.11%,0.19%,0.30%Si,0.10%,015%,0.21%,0.26%Sn respectively,have been measured by using PS-168C electrochemistry measurement system in 35 g/L NaCl solution.The surface morphology of the samples after corrosion test was observed by SEM.Compared with the experimental result of ZA27 alloy,it is shown that the free corrosion potential of all the tested alloys shifts to negative and the their corrosion current densities increase with impurity elements addition.And impurity elements decrease corrosion resistance of ZA27 alloy.The effect of Sn is greater than that of Si.