Influence of carbon fiber prepreg layup on electromagnetic interference shielding and thermal conductivity of composite

Abstract Electronic components produce severe electromagnetic radiation and heat, which affect their normal operation and the health of humans. The prepreg material with domestic high strength and high modulus M55J carbon fiber (CF) as filler and epoxy (EP) resin as matrix was adopted. The arrangement of CF within the resin matrix was modified by adjusting the angle of the prepreg cross‐layup. Finally, the effect of CF arrangement on the electromagnetic shielding and thermal conductivity of the composites was investigated. Based on the results, the prepreg laminates with a 90° cross angle exhibited an electromagnetic shielding effectiveness of 38 dB in the X band, outperforming those with other cross angles. The issue of uneven in‐plane thermal conductivity has been alleviated by the prepreg laminates with a 90° cross angle. Its in‐plane thermal conductivity reached 20.8 W/(m K). The thermal conductivity in the thickness direction of prepreg laminates is around 1 W/(m K). This proves that the cross angle does not affect the thermal conductivity in the thickness direction of the laminates. The in‐plane and through‐thickness thermal performance of prepreg laminates is primarily determined by the anisotropy of the CF. Prepreg laminates with a 90° cross‐ply configuration demonstrate better performances in thermal conductivity and electromagnetic shielding. In this study, the influencing factors of the layered structure on the electromagnetic interference (EMI) shielding and thermal conductivity of composite laminates are discussed, which can provide a theoretical basis for the structural design of dual‐function composite with both thermal conductivity and EMI shielding. Highlights Fabrication of CFRP laminates with systematically varied cross‐ply orientations. Functional relationship between the orientation and arrangement of CFs and the I ₀₀₂ / I ₁₀ ratio (XRD). The optimal electromagnetic shielding performance and its mechanism of CFRP laminates. Improvement of heat dissipation within the plane.