University of Missouri-Columbia Center for Physical and Power Electronics Columbia United States
During the period of performance we investigated the electrical and mechanical properties of two types of ferrite metamaterials ferrite-based composites and core-shell composites. Both were fabricated using advanced polymer composite techniques and then characterized. The measurements were compared to models and the analysis is presented in this report. The ferrite-based composites consist of combining a ferrite powder with a silane binder and pressing them together following a mixing operation. These composites are easily manufactured in bulk and their properties can be tailored to specific wave impedance requirements. In the other approach, the core-shell composites are formed by chemically depositing a barium titanate BaTiO3 shell around a ferrite core to form a composite of small beads of ferrite surrounded by insulating BaTiO3. Both metamaterials were then fabricated into test coupons and the electrical properties were investigated. Investigations of electrical properties included studies of real and imaginary permeability of the composite materials studies of real and imaginary permittivity of the composites electrical breakdown strength of the composites.