Effects of extreme surface roughness on 3D printed horn antenna

3D printing is an emerging technology in manufacturing. It is the long-term goal of the industry to print complex and fully functional products from cell phones to vehicles. A drawback of many 3D printing technologies is rough surface finish. It is known that metals with high surface roughness severely degrade the propagation of electromagnetic waves. Presented is the first known evaluation of the electromagnetic impact of the typical surface roughness in metal parts produced by electron beam melting. Two Ku-band (12–15 GHz) horn antennas were 3D printed, with different surface roughness, and compared to a standard horn antenna purchased from Pasternack.