DC Electric Metamaterial Behavior in Fused Filament Fabrication Prints With Tuned Interfaces

DC Electric metamaterials are interesting for electronics, sensors, and actuators by enabling steering of current. In this article, we realize such dc electric metamaterials with fused filament fabrication (FFF) by tuning the nozzle temperature, bed temperature, and extrusion width to achieve anisotropic electrical conduction. Both temperatures influence the magnitude of the contact resistance between printed lines, whereas the extrusion width determines the number of interfaces per unit length. An anisotropic effective medium approximation (EMA) model is used to analyze the effect of the electrical parameters and is verified with finite element (FEM) simulations. Measurements are performed with a setup inspired by the pseudo-Hall effect. Finally, exploiting the anisotropic properties of 3-D printed conductors, we present a current concentrator and its operation is demonstrated through IR thermography and voltage measurements.