Monolithic Q-band Waveguide Filter using 3D-Printed Silver

This paper presents the design, fabrication, and measurement of a Q-band waveguide bandpass filter fabricated using 3D-printed sterling silver. While aluminum alloys are common in additively manufactured microwave components, silver offers superior electrical and thermal conductivity. A stepped-impedance waveguide filter was fabricated using optimized Laser Powder Bed Fusion parameters to achieve high density and conductivity. RF measurements demonstrated a 0.8 dB minimum insertion loss and 17 dB worst-case return loss within the 37.5–42.5 GHz band. These results validate the feasibility of silver 3D printing for high-performance microwave devices.