Composite Materials Development for Fused Filament Fabrication of RF Systems

In this paper we present the development of feedstock materials, specifically tailored permittivity materials used in fused filament fabrication (FFF), for microwave applications. One of the major bottlenecks in utilizing additive manufacturing for useful radiofrequency (RF) applications is the lack of suitable materials. Flexible, high-dielectric constant and low dielectric loss tangent composite materials, consisting of a mixture of polymer and ceramic nanoparticles in controlled volume fractions, are manufactured. Effective medium approximations (EMA) to predict composite properties, such as Bruggeman approximations, are validated with measurements between 18-40 GHz and are presented.