Assessment of the shielding efficiency of FDM-produced continuous carbon fiber composites

With the accelerating advancements across diverse sectors related to electronics, including telecommunications, automotive industries, and data centers, the issue of electromagnetic interference (EMI) is becoming increasingly critical. Such interference can lead to malfunctions or failures in electronic systems or components. Thus, the housing of an electronic system must not only provide robust mechanical properties but also maintain an effective electromagnetic shielding. The use of carbon-based composite materials appears to be a promising approach to meet these needs, allowing for the creation of an efficient lightweight housing at a reduced cost. Numerous studies have been conducted on polymers filled with carbon black, carbon nanotubes, or microfibers. In this paper, we focus on the use of continuous carbon fibers produced by fused deposition modeling (FDM) and investigate their shielding effectiveness in the X-band (8.2 GHz to 12.4 GHz) through waveguide measurements. The shielding effectiveness of materials with varying carbon content was evaluated. The effect of the printing direction of continuous fibers relative to the electric field was also investigated. Finally, the material’s permittivity was calculated using the NRW method to generate a model for conducting simulations in the X-band, targeting various applications where electromagnetic shielding is essential.