Evaluation of Additive Manufacturing Techniques Applied to a Waveguide Mode Transducer

This article presents a detailed comparison between the classic manufacturing technology by computer numerical control (CNC) and the disruptive additive manufacturing (AM) technology by means of selective laser sintering (SLS). Three different implementations of a mode transducer from the TE10 rectangular waveguide mode into the TM01 circular waveguide mode at Ku-band have been manufactured, each one using a different technology. Their experimental performances are compared with respect to effective conductivity, insertion and return losses, weight, cost, and delivery time. The first technology under analysis was high precision milling by CNC using aluminum. The second one was AM-SLS using AlSi10Mg aluminum alloy powder. Finally, the third one was also SLS, but using CuNi2SiCr, an alloyed copper-material with electrical conductivity after precipitation hardening of 23 MS/m. In order to verify the theoretical simulations, a back-to-back arrangement using two transducers was measured in all three cases. A detailed comparison and a final table highlighting the advantages and drawbacks found for each technology are presented, which can be used as a reference for other similar waveguide components.