Ultra-thin and Light-weight Ceramic-based Film for High-Efficiency Electromagnetic interference shielding at High Temperature

Flexible, lightweight, ultra-thin, and high-temperature-resistant electromagnetic interference (EMI) shielding materials are of paramount importance for high-speed aircraft to eliminate external electromagnetic interference. However, current high-temperature-resistant electromagnetic shielding materials are primarily restricted to rigid and thick ceramic plates, which fail to provide both lightweight and flexible properties. Aiming at the compatibility problem of flexible and high-temperature resistance, a composite structure resembling bird-nest was designed. The structure enhanced the mechanical properties of inorganic fiber films and boosts the anti-oxidation capability of carbon fibers at high temperatures. This flexible, lightweight (~0.3 g/cm³), ultra-thin (~0.35 mm) composite film was developed utilizing the high-temperature-resistant properties of silica fiber and the shielding effect of carbon fiber. Within 2.6-18 GHz, the silica-carbon composite film exhibits an exceptional specific EMI shielding effectiveness of 92.6 dB/mm at room temperature and a high average high-temperature EMI shielding effectiveness exceeding 30 dB at 650°C. This work has significant implications for the advancement of electromagnetic shielding at high-temperature components within both civilian and military sectors.