混合稀土铅合金金相结构和阳极氧化膜的研究

摘要

The metallographic structure of Pb-(0.001％,0.005％,0.01％,0.1％,0.2％) mixed La and Ce rare-earth alloys was studied by means of metallography microscope.It can be seen that homogeneous single phase solid solution is obtained when the mixture of La and Ce is added to the lead alloy,and the crystalline grain is refined by order of magnitude;as a result,the ductility and toughness of the lead alloy are improved.The anodic behavior of Pb-La-Ce alloys in sulfuric acid solution were studied by means of linear sweep voltammetry (LSV),cyclic voltammetry(CV) and constant current corrosion tests,respectively.The results show that the mixed rare-earth (La and Ce) can inhibit the growth of the anodic Pb(Ⅱ) oxides and can also decrease the impedance of oxide film on the surface of lead alloy.When the content of the mixture of La and Ce is lower than 0.01％,the growth of PbO2 on the grid alloy is facilitated,and adverse affect will appear when the additive amount is higher.A proper content of rare earth can improve the corrosion resistance of the grid alloy and suppress the evolution of hydrogen and oxygen.When the mass radio is 0.1％,an optimum property is obtained.%采用金相显微镜、电子扫描电镜(SEM)、线性电位扫描(LSV)、循环伏安(CV)、恒电流腐蚀等技术和方法研究了不同镧铈混合稀土含量的铅合金金相结构和在硫酸溶液中氧化膜的生成情况.研究结果表明,在铅合金中添加适量镧铈混合稀土可以明显细化合金晶粒,使板栅合金有更好的塑性和韧性;镧铈混合稀土添加剂能够抑制深放电时阳极高阻抗的Pb(ll)氧化膜生长,有利于提高电池的充放电性能;镧铈混合稀土添加剂还可以抑制浮充电位时(1.3 V)的阳极PbO2的生长,提高合金的耐腐蚀性能.