3D Printing as a Rapid Prototyping Approach for Novel RF Cavity Designs

Abstract

3D-printing of radiofrequency (RF) cavity resonators could provide a cost-effective solution that enables rapid prototyping and design flexibility compared to traditional fabrication of full-metal cavities. In this work, the feasibility of fabrication of a useful multi-mode GHz cavity is explored. Two kinds of plastics, two slicing approaches and two metal coating techniques were used to build a series of clamped cavities with thin inner copper surface on otherwise 3D printed plastic surface. The cavities were then bench-tested to identify spatial field distributions, operating frequencies and quality factors (Q-factor). Pros and cons of the used fabrication approaches were identified and understood, and the performance of longitudinally sliced painted cavity design demonstrated considerable practicality of 3D-printing approach in designing rf systems.

Figures (8)

• Figure 1: The concept of TM$_{010}$ (blue) and TM$_{011}$ (orange) superposition highlighting the linearization of the $E$-field.
• Figure 2: 3D models of two distinct cavity slicing: (a) longitudinal and (b) latitudinal where nose cones blocking sputtering are shown in red. (c) Another rendering of blockade locations due to the complex nose cone geometry.
• Figure 3: Diagram of the three assembled and tested cavities.
• Figure 4: Conceptual diagram of the bead-pull testing setup/procedure.
• Figure 5: Relative $E$-field for TM$_{010}$ mode.