Prototype manufacturing of microwave components using plastic 3D printing

Abstract: The ability to easily customize and produce specialized MW-components for research and industry is a real challenge and the need is identified, as standardized parts have limited use and can limit design freedom. This study aims at exploring if there are simple ways to manufacture rectangular X-band waveguides with operating frequency of 8-12GHz with novel polymer additive manufacturing and chemical metal deposition that can match Computer Numerical Control (CNC) manufactured rectangular metal waveguides in performance. X-band was chosen mostly because of it having a good size to start printing trials and x-band components being in heavy use where a lightweight would be beneficial. Also, to evaluate the manufacturing results by measuring and comparing s-parameters and weight between measuring standard and manufactured waveguides. Furthermore, to use the preexisting models for approximating the attenuation due to surface roughness. Different designs were tested with different polymers and electrodeposition techniques and approaches. Two of the benchmarked techniques gave better results; first, using a modular design with a combination of different polymers and an industrial copper plating technique; second, a single polymer one-piece design using an acrylic carbon paint and a small scale in-house electroless copper deposition. The performance of conventionally manufactured rectangular metal waveguides was not matched but the two investigated techniques show on results that the techniques could possibly be modified in the future to match the performance of conventionally manufactured waveguides.