有机酸对铝箔阳极氧化膜微观结构与性能的影响  

Effect of organic acid on microstructure and properties of anodized alumina film on Al foils

作　　者：班朝磊[1,2] 何业东[2] 邵鑫[1] 王长征[1] 杜鹃[1] 

机构地区：[1]聊城大学材料科学与工程学院,山东聊城252059 [2]北京科技大学北京市腐蚀磨蚀与表面技术重点实验室,北京100083

出　　处：《材料热处理学报》2012年第12期137-141,共5页Transactions of Materials and Heat Treatment

基　　金：北京地区高等学校新材料学科群建设项目;聊城大学博士科研启动资金(31805)

摘　　要：将高压铝电解电容器用腐蚀铝箔分别在硼酸溶液、硼酸+微量苯甲酸、硼酸+微量柠檬酸和硼酸+微量酒石酸溶液中进行阳极氧化制得耐压薄膜;应用透射电镜(TEM)对比研究了硼酸液中添加上述微量有机酸前后所形成阳极氧化膜的厚度与微观结构,应用大功率X-射线衍射(XRD)仪分析了氧化膜的结晶程度,应用LCR数字电桥和小电流充电测试了氧化膜的比电容和耐压值。结果表明:硼酸溶液中微量有机酸的添加有利于促进高结晶度阳极氧化膜的形成;随着溶液酸性的增强,氧化膜晶粒平均尺寸逐渐增大、形成常数降低、获得高比电容值;同时氧化膜相变收缩加剧、内应力增大、氧化膜内部缝隙微观缺陷密度增大,导致氧化膜耐电压值降低。Barrier anodized alumina films on etched A1 foils for high voltage aluminum electrolytic capacitors were prepared by anodization in boric acid solution,boric acid ＋ benzoic acid solution, boric acid ＋ citric acid solution and boric acid ＋ tartaric acid solutions. The films obtained were examined by TEM and high power XRD to study its thickness,mierostructure and crystallinity. The special capacitance and withstanding voltage of the films was measured with LCR meter and small-current charging. The results show that the addition of trace strong organic acids in boric acid solution can contribute to formation of high erystallinity films. With increase in the electrolyte acidity,the crystallites of the films generally increase in size and its formation constant decreases,leading to an increase in the special capacitance. Meanwhile, due to phase transformation, there are more defects and higher internal stress in the mixed acids-formed films than that in the boric acid only formed film,leading to a decrease in its withstanding voltage.

关 键 词：阳极氧化 铝箔 电解电容器 有机酸 微观组织 

分 类 号：TG172.8[金属学及工艺—金属表面处理]