High Specific Volume Of Anodized Aluminum Composite Membrane Voltage Resistance Mechanism

Aluminum electrolytic capacitor can not be replaced in electronic machine system, the core component of which is alunminum anodic oxide film. The preparation and formation mechanism of alunminum anodic oxide film are hot research topics in the industry. In this paper, the research of the withstanding voltage of composite alunminum anodic oxide film base on the Ion Mobility Method, the key factors of withstanding voltage and leakage current of composite film were analysed, and a new preparation of composite alunminum anodic oxide film was proposed.A withstanding voltage model of (+)Al/Al2O3/ electrolyte(-) system was built, in this system, testing current of withstanding voltage was separated into charge current and leakage current. The curve of withstanding voltage with time could be simulated by this model, and this model enabled us to explain withstanding voltage curve of aluminum anodic oxidation film. The calculation revealed that step time and value of withstanding voltage could be accurately calculated by this model. The withstanding voltage data of composite alunminum anodic oxide film was analysed, the calculation revealed that there were a lot of defects in composite film prepared by tranditional preparation. Defects resulted the decreasing of withstanding voltage and the increasing of leakage current of composite film. Al2O3-TiO2 composite film was prepared by cathodic electro-deposition process. The cathodic electro-deposition process was helpful for increase the surface adhesion between TiO2 deposition and aluminum palte, and the composite film had higher dielectric constant and less defects.