硅和锡对ZA27锌基合金耐腐蚀性能的影响

Effects of Si and Sn on Corrosion Resistance of ZA27 Alloy

摘要: 在35 g/L NaCl水溶液中,用电化学测量系统测定了硅加入量分别为0.11%,0.19%,0.30%和锡加入量分别为0.10%,0.15%,0.21%,0.26%的ZA27锌基合金的塔菲尔曲线、腐蚀电位、线性极化电阻和腐蚀电流密度等电化学参数,在扫描电镜下观察了腐蚀后的形貌,并与二元ZA27合金进行了比较.结果表明:硅和锡的加入使试验合金的腐蚀电位朝负向移动,腐蚀电流密度增加,均降低了ZA27高铝锌基合金的耐腐蚀性能,其中锡的影响较大.

Abstract: 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.