Metallic 3-D Printed Rectangular Waveguides for Millimeter-Wave Applications

This paper explores the potential of metallic 3-D printing technology for millimeter-wave (mmWave) applications. It uses the selective laser melting (SLM) technology to melt the Cu-15Sn powder layer by layer to build up rectangular waveguides at E(60-90 GHz), D(110-170 GHz), and H-band (220-325 GHz). Different from nonmetallic 3-D printed waveguides, SLM Cu-15Sn waveguides are printed once in a whole piece. Post-electroplating and assembling are not necessary. Besides, the SLM waveguide also outperforms the nonmetallic 3-D printed waveguide in mechanical robustness. Compared with nonmetallic 3-D printed and commercial metallic waveguides, SLM waveguides demonstrate comparable performance at E-band with averaged dissipative attenuation 7.51 dB/m and 7.76 dB/m for 50and 100-mm waveguides, respectively. The attenuation of SLM waveguides is acceptable up to D-band. We prove the potential of the SLM technology for mmWave applications in both prototyping and mass production.