Ag和RE含量对Pb-Ag-RE合金阳极电化学性能的影响  

Effects of Ag and RE contents on electrochemical performance of Pb-Ag-RE alloy anode

作　　者：桂俊峰[1] 蒋良兴[1] 钟晓聪[1] 于枭影[1] 赖延清[1] 李劼[1,2] 刘业翔[1] 

机构地区：[1]中南大学冶金与环境学院,长沙410083 [2]中南大学难冶有色金属资源高效利用国家工程实验室,长沙410083

出　　处：《中国有色金属学报》2015年第1期111-118,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家"十二五"科技支撑计划课题(2012BAA03B04);国家自然科学基金资助项目(51204208;51374240);湖南省自然科学基金资助项目(13JJ1003);第54批博士后科学基金资助项目(2013M540638)

摘　　要：采用恒流极化、计时电位、塔菲尔曲线、扫描电子显微镜(SEM)和X射线衍射(XRD)对比研究不同Ag和RE含量Pb-Ag-RE合金阳极的析氧行为和腐蚀行为。结果表明:减少Ag含量将导致阳极析氧过电位升高,阳极的腐蚀速率增大。RE的加入有利于促进高阻抗成分Pb SO4、Pb O向α-Pb O2和β-Pb O2转化,进而提高阳极的析氧活性,降低阳极电位。此外,RE可以提高氧化膜的致密度,细化Pb-Ag合金的晶界和枝晶界,减轻合金基底的晶间腐蚀。因此,RE可以有效改善Pb-Ag合金阳极的析氧活性和耐腐蚀性能,微量的RE可以部分取代Pb-Ag阳极中的Ag。The oxygen evolution and corrosion behaviors of Pb-Ag-RE anodes with different Ag and RE contents were investigated using galvanostatic polarization, chronopotentiometry, Tafel curves, scanning electronic microscopy （SEM） and X-ray diffractometer （XRD）. The results show that the reduce of the Ag content leads to the increase of the oxygen evolution overpotential and corrosion rate. The addition of RE benefits to the formation of a dense anodic layer, and then reduces the corrosion of metallic substrate. The RE addition facilitates the transformation of high resistance PbSO4 and PbO toα-PbO2 andβ-PbO2, which further helps to enhance oxygen evolution reactivity and reduce anodic overpotential. In addition, RE can improve the compactness of the anodic layer, refine the grain and interdendritic boundaries of Pb-Ag alloy and diminish the interdendritic corrosion of metallic substrate. Consequently, RE can effectively improve the oxygen evolution reactivity and corrosion resistance, trace amounts of RE can partly replace Ag of Pb-Ag anode.

关 键 词：铅基阳极 稀土 电沉积 腐蚀 析氧 

分 类 号：TF813[冶金工程—有色金属冶金]