Electrical Conductivity Measurement on Metallic Materials With a Cylindrical Resonator

This article presents a novel method for measuring the electrical conductivity of metallic materials using a cylindrical resonator. The theory and the process of measuring the electrical conductivity are explained. The cylindrical resonator is designed and proved using full-wave electromagnetic simulations. A prototype operating at 10.5 GHz is fabricated, and the scattering parameters are measured. The quality factor of the cylindrical resonator is calculated at the first step from the measured scattering parameters, and the electrical conductivity of the metallic material is derived using Maxwell's equations. By replacing the top cover of the cylindrical resonator with different materials or metallic sheets, the electrical conductivities can be measured easily. For validating the method, three top covers and six metallic sheets are fabricated and tested. The measured electrical conductivities are compared with other published results and typical values. Besides, by adjusting the operating frequency of the cylindrical resonator, the proposed method can be applied to determine the electrical conductivity at specific frequencies.