Low-Cost Ku-Band Waveguide Devices Using 3-D Printing and Liquid Metal Filling

This paper presents a simple, low-cost, hours-long fabrication method for microwave waveguide components of high RF performance. The technique combines 3-D-printed configurations with liquid metal waveguide structures. As a demonstration, a fused deposition modeling multimaterial 3-D consumer-grade printer and liquid gallium were used. A conductive polylactic acid (PLA) waveguide flange was 3-D printed along, in-one-go, with standard PLA for the rectangular waveguide liquid metal enclosures. Microwave WR62 waveguides, resonators, and filters operating in Ku-band were designed, fabricated, and tested. The RF performance of the fabricated waveguide devices is in agreement with the simulations demonstrating better than 1.29 dB/m attenuation in the waveguide and better than 1000 Q-factor for the resonator and the filter at 13 GHz. The fabricated devices demonstrate a new option of an economical fabrication technology for high RF performance microwave waveguide-based devices that can be delivered in hours-time, anywhere, anytime with minimal equipment deployment and investment.