酸碱预处理对高压电子铝箔腐蚀扩面的影响

目的研究高压电子铝箔在Na OH和HCl溶液中的电化学行为,分析酸、碱预处理对铝箔电化学腐蚀扩面效果的影响。方法比较铝箔在不同浓度Na OH,HCl溶液中的预处理效果。采用极化曲线获得铝箔在各预处理溶液中的电化学参数,研究其腐蚀行为。利用扫描电子显微镜观察预处理后铝箔的表面形貌,分析预处理对铝箔表面形貌的影响。观察铝箔腐蚀扩面后的蚀孔形貌及蚀孔分布,分析预处理对蚀孔的影响。结果预处理减弱了铝箔制造过程中形成的表面不均匀,提高了表面活性,使得铝箔在电化学腐蚀处理中蚀孔密度增加,分布均匀。对未预处理铝箔及经HCl和Na OH预处理的铝箔进行电化学扩面处理,发现相对于未预处理的铝箔(比电容为0.56μF/cm2),经HCl溶液预处理的铝箔比电容提高了4%~8%,Na OH溶液预处理的铝箔比电容提高更为明显,约为13%~16%。铝箔在HCl溶液中的自腐蚀电位约为-820 m V,在Na OH溶液中的自腐蚀电位约为-1720 m V,并且经计算得知,铝箔在Na OH溶液中比在HCl溶液中自腐蚀速率快。结论铝箔在Na OH溶液中腐蚀均匀,用Na OH溶液对铝箔进行预处理,可以消除铝箔轧制缺陷,提高铝箔的比电容。

Effect of Alkaline or Acidic Pretreatment on the Etching Area-enlarging Process of High-voltage Electron Aluminum Foil

Objective To investigate the electrochemical behavior of high-voltage electron aluminum foil in HCl and NaOH solu-tion, and the effect of alkaline or acidic pretreatment on the area-enlarging of electrochemical etching of the aluminum foil. Methods This study compared the pretreatment effect of aluminum foil in different concentrations of HCl and NaOH solution. The electrochemical parameters of aluminum foil in different pretreatment solutions were obtained with polarization curves by which the etching behavior of aluminum foil was analyzed. The morphology observation of aluminum foil surface by means of scanning electron microscope ( SEM) was used to analyze the influence of pretreatment on the surface morphology. The morphology and distribution of the pitting etching hole were observed to analyze the effect of pretreatment on the pitting. Results The pretreatment reduced the microstructure inhomogeneity on the foil surface formed during the manufacturing process and improved the surface activity, which increased the pit density and uniformity of pit distribution. The special capacitance of all experimental aluminum foils after electro etching process showed that compared with the primary aluminum foil (the specific capacitance was 0. 56 μF/cm2), the specific capacitance of foil with HCl solution pretreatment increased by 4% ~8%;whereas the specific capacitance of foil with NaOH solu-tion pretreatment increased by about 13% ~16%. The self-corrosion potential of aluminum foil in HCl solution was about -820 mV, while the self-corrosion potential in NaOH solution was obviously lower, about -1720 mV. Compared with that in HCl solu-tion, the self-corrosion rate of aluminum foil in NaOH solution was faster. Conclusion The more uniform corrosion in NaOH solu-tion could eliminate the rolling defects of aluminum foil and improve the specific capacitance of aluminum foil.