高纯电容铝箔中残留杂质化合物的研究

来源期刊：中南大学学报(自然科学版)1986年第3期

论文作者：崔祺 张伟斌

文章页码：39 - 46

关键词：电容铝箔； 杂质化合物； 比电容

Key words：High purity aluminium foil for electrolytic capacitors； Impurity compounds； Specific capacitance

摘    要：本文通过电镜观察和电子计算机运算,标定了高纯电容铝箔经不同温度淬火后残留杂质化合物的成分和结构,同时研究了电阻率、显微硬度随热处理条件而变化的规律。TEM观察表明:500℃/5min淬火后,残留化合物有FeAl₆、FeAl₃,α-AlFeSi和其它杂质粒子。500℃/min淬火后,残留化合物有(AlFeSi)T相粒子和其它杂质粒子。600℃/5min淬火,没有杂质粒子存在。由电阻率和显微硬度的变化规律说明,杂质粒子在淬火过程中发生溶解。完成溶解过程所需要的时间随淬火温度上升而缩短,在500℃时约15min,550℃时约10min,600℃时约5min。杂质的存在状态对铝箔比电容影响很大。SEM观察表明:杂质以第二相粒子形式存在将造成腐蚀不均,比电容下降。杂质固溶于铝基体中,腐蚀不均现象可以避免或减弱,比电容上升。

Abstract: The impurity compounds which remained in high purity foil quenched atdifferent temperatures were observed with TEM. The composition and struc-ture of these compounds have been determined by TEM and computer. Theregulation of resistivity and michardness change related to the heat treat-ment condition have been found out. TEM analysis showed: (1) FeAl₆, FeAl₃, α-AlFeSi particles remained in the foil quenhed at 500℃/5 min; (2) (AlFeSi)Tparticle and some impurity partciles remained in the foil quenched at 550℃/5min; (3) no impurity particles remained in the foil queneched at 600℃/5min. The regulation of resistivity and michardness change showed that thesecond phase partcles were dissolved into Al matrix at quenching, and thetime reaching equilibrium concentration decreased as quenching temperature wasraised, for instance, 15 min at 500℃, 10 min at 550℃, 5 min at 600℃. Theeffect of the impurity states on specific capacitance of the foil was great. Theresults obtained in observation of the etched foil morphology with SEM showedthat if the impurity existed at a state of second phase particle, the foil would beetched ununiformly and the specifie capacitance would be decreased; on theother hand, if the impurity dissolved into Al matrix, ununiformity etchingwould be avoided or reduced, and specific capacitance would be raised.