Publication

Abstract : Coaxial transmission line-based technique to explore suitability of dielectric powders as fillers for cement-based EMI shielding is presented, in frequency range 100MHz−1GHz. Low frequency characterization mandates large antennas and huge samples. The proposed technique provides rapid initial estimates on EMI shielding performance of powders, enabling easier filler identification, reducing cost and time. Dielectric fillers considered are ash by-products from varied units of steel plants including Argon-Oxygen Decarburization (AoD), Acid Recovery Station (ARS) and Electric Arc Furnace (EAF) units. Plane wave skin depth of powders is computed from S matrix measurements on ash filled coaxial structure. The coaxial line includes provision to vary dielectric material. ARS ash exhibits skin depth less than 20 cm in entire frequency analysis range. AoD and EAF ashes provide good skin depths less than 40 cm in the upper UHF range above 500 MHz. Validation of results though plane wave experiments are necessary. Industrial and agriculture by-products in powder form, which are at present explored as sustainable options, can be easily characterised through the present technique, for customized EMI mitigation solutions, and for other emerging cement based applications in electrical engineering.