Electromagnetic characteristics of 3D-printed composites by free-space measurement

This paper aims to assess the electromagnetic (EM) characteristics of 3D-printing composites based on contin-uous fiber and infill material in the X-band (8.2-12.4 GHz) using the free-space measurement (FSM) system. Firstly, the EM properties of the 3D-printed composite specimens can change depending on type and thickness of the infill material. Especially, Onyx (Chopped carbon fiber/Nylon) and Onyx ESD (Static-dissipative chopped carbon fiber/Nylon) exhibit a change in EM properties according to thickness due to randomly dispersed micro-sized chopped carbon fibers. Secondly, when fabricating a 3D-printed composite specimen containing continuous fiber layers, the top and bottom layers always consist of infill material. As the EM characteristics of both continuous fibers and infill materials depend on their type and thickness, it is crucial to select appropriate materials and thicknesses for 3D-printed composite specimens with continuous fiber layers. The EM character-istics of 3D-printed composites can also aid in designing multi-functional 3D-printed composite structures that require not only mechanical but also EM performance.