Fe、Si杂质含量对电解电容器低压阳极铝箔静电容量的影响

Ｆｅ在高纯铝中的存在状态（固溶状态或Ａｌ３Ｆｅ，ＡｌＦｅＳｉ金属间化合物析出状态）直接影响铝在盐酸溶液中的腐蚀速度，从而对腐蚀箔的静电容量有极大影响。介绍了近年来日本专利中关于防止Ｆｅ、Ｓｉ析出的轧箔工艺，即高温固溶处理后在数分钟内完成热轧，使Ｆｅ、Ｓｉ来不及析出，这样，９９．９８％Ａｌ就其Ｆｅ、Ｓｉ析出量而言，实际可达到９９．９９％以上铝的水平。更进一步，控制Ｆｅ、Ｓｉ析出分布状态（弥散状分布）的轧箔工艺，有可能用９９．９３％～９９．９８％铝得到９９．９８％以上纯度铝同样静电容量水平。

Effect of Impurity Fe and Si Content on the Capacitance of Anode Aluminum Foil in Low Voltage Electrolytic Capacitor

The existence state of Fe in high purity aluminum foils (as in solid solution or in precipitation phase of intermetallic compounds Al3Fe and AlFeSi ) has great effect on their etching rates in hydrochloricacid, and hence on the capacitance of etched foil. The manufacturing technology of aluminum foil appeared in recent Japanese Patents was introduced, this technology prevents the impurity Fe from precipitating into a second phase during hot and cold rolling process, and thus an aluminum foil in purity of ≤9.98% can be used as an anode electrode in low voltage electrolytic capacitor with the same level of capacitance (value) of purity ≥99. 99% foil.