Investigation on the Effect of Roughness of 3D Printed Structure on Performance of Microwave Devices

In this paper, 3D printed X band waveguide are proposed with epoxy coating as the conductor. Since the 3D printed structures end up having rough surfaces due to laying separate layers of the melted plastic on top of each other, this phenomena should be also considered in the simulation model. The roughness of the surface depends on the printing tip dimensions and the printing conditions. The whole structure is printed with a 3D printer and then is dipped into a low viscosity conductive solution to form the conductive layer on the inner walls of the waveguide. The waveguide system then is fed using coaxial cables. The results show the roughness can influence the transmission loss especially if the conductivity of the coated conductor layer is not as high as the conventional waveguide.