Plastic and metal additive manufacturing technologies for hyperfrequency passive components up to Ka band

This paper illustrates the different possibilities given by additive manufacturing technologies for the creation of hyperfrequency devices. Firstly a characterization campaign has been made on common plastics used by 3D printer using the Fused Deposition Modeling (FDM) and material jetting (Polyjet©) technologies. The impact of the manufacturing strategy (high speed or high accuracy) on the part roughness, as well as on the dielectric material permittivity and loss tangent has been specifically studied at 10 and 16 GHz. The conductivity of a coating based on a silver paint has also been characterized on such plastic parts. These plastic materials and coating have been used for the creation of a quasi-elliptic bandpass filter centered at 6 and 12 GHz and compared to a similar filter made of stainless steel by selective laser melting. Finally, a compact rectangular TE
₁₀
to circular TE
₀₁
mode converter also made by selective laser melting is illustrated here from 28 to 36 GHz as a final demonstrator.