Impedance measurements on lacquered tinplate: fitting with equivalent circuits

摘要: Experimental impedance data previously obtained for various kinds of lacquered tinplate are fitted using two different equivalent electrical circuits, with the aim assessing advantages/disadvantages this procedure quality control material as compared to direct evaluation diagrams. It is shown that screening purposes same conclusions can be either by fitting or qualitative analysis The physical meaning parameters from measurements also discussed. results interpreted on basis lacquer characterized intact and porous areas which associated a capacitance in parallel pore resistance high frequency range. At lower frequencies other processes occur series pores. For short immersion times, passivation film present detected, whereas longer faradaic detected.