(1. 四川大学化工机械系; 2. 金材系,成都610065)
摘 要: 研究了在HCl溶液中50Hz交流电侵蚀下电流密度对电解电容器用高纯铝箔的腐蚀行为的影响。结果表明,侵蚀初期的真实电流密度决定铝箔蚀孔的尺寸和表面膜,大电流在铝箔表面产生厚膜,阻碍交流电侵蚀的阴、阳极反应过程和蚀孔深入。随着电流密度减小,试样的蚀孔孔径增大,在<0.2 A/cm2电流下的蚀孔比其它大电流下的蚀孔孔径大4倍左右。先用<0.2 A/cm2的小电流侵蚀,再用0.2~0.5A/cm2大电流侵蚀组合,铝箔电容量随电量的增加直线上升。用50 Hz交流电可以使铝箔获得良好的起始发孔,得到具有较大孔径和多向堆垒型海绵层蚀孔的大容量电解电容器用铝箔。
关键字: 铝箔;侵蚀;孔蚀
(Department of Chemical Engineering Machinery, Sichuan University, Chengdu 610065, P.R.China)
Abstract:Aluminum foil for low voltage aluminum electrolytic capacitors was etched by different current density of 50 Hz AC in hot choleric solution. The results showed that the current density of AC has definite effect on the initial pit growth size and etch film of pits in etched Al foil. Using AC 0.3~0.5 A/cm2, the potential peak-peak value of E-t was about 2.4 V and the break down potential E p was about 1.0 V, but using AC<0.2A/cm2 , the potential peak-peak value was only 0.7V and the Ep was only 0.4 V. It was showed that the thicker etch film was formed by bigger current. The size of cubic pits in AC<0.2A/cm2 was 4 times larger than that in other bigger AC current density. Etching combined current density may get etch pit of bigger aperture and etch aluminum foil of bigger capacitance, first step using AC<0.2A/cm2, and second step using AC 0.2~0.5A/cm2,the larger area and capacitance of etched aluminum foil can be obtained by 50Hz AC.
Key words: aluminum foils; etching; pitting