电解工艺条件对铝箔腐蚀形貌与比电容的影响

利用扫面电镜(SEM)、数字电桥研究了铝电解电容器用高压电子铝箔在硫酸+盐酸体系中进行电化学腐蚀扩面时,工艺条件对铝箔腐蚀形貌与比电容的影响规律:电解腐蚀时间对铝箔腐蚀后形貌与比电容影响较大,发孔时间延长、扩孔时间缩短,隧道孔密度增加、孔直径减小；发孔电流密度对铝箔腐蚀形貌与比电容影响较小,只要高于点蚀电流密度,小电流长时间发孔与大电流短时间发孔都可以在铝箔表面形成足够密度的蚀孔结构；电解液温度对铝箔腐蚀形貌和比电容影响较大,随着发孔液温度的提高,蚀孔密度增加、蚀孔孔径减小,隧道孔长度减小.

Effect of electro-etching parameters on morphologies and specific capacitance of aluminum foil

The influence of electro-etching technological parameters during H2SO4-HCl electrolyte on surface and cross section morphology and specific capacitance of high voltage aluminum foil used for aluminum electrolytic capacitor has been studied by using of SEM and digital electron bridge.The results show that the etching time affect morphologies and specific capacitance of etched aluminum foil greatly,pit dropping time being elongated,pit-initiation time being shorted,pit density being increased and the pit diameter being decreased;the etching current-density affect morphology and specific capacitance weakly,the sufficient pit density can be obtained on the aluminum foil surface both at the conditions of low current with long etching time or high current with short etching time while the current density is higher than pit-initiation current;the electrolyte temperature affects morphology and specific capacitance of aluminum foil greatly,the etched pit density is increased,the pit diameter and the pit depth are decreased with electrolyte temperature increasing.