Development of a modified test cell for AC impedance testing of coated Al fins

Abstract

An innovative test-cell arrangement is proposed and examined for electrochemical impedance spectroscopy (EIS) testing of coated thin sheet or foil samples. This arrangement uses a thin layer of medical cotton fabric as a medium containing and transporting 5% sodium chloride solution. This new EIS cell avoids the intervention of edge effect into EIS measurements of painted material. It also avoids the formation of crevice attack experienced at the edges of conventional sample holders or normally under the edge of the masking material. This arrangement is simple and flexible to suit different sizes and shapes of flat panel and foil samples. It can also be used effectively as specimen holders for other than thin sheets. The test cell is also suitable for any electrochemical tests other than impedance measurements. The accelerated results of the EIS present the viability of the EIS test cell to be used as an accelerated nondestructive, repetitive measurement of coated thin metal substrate.