MULTIFUNCTIONAL CERAMIC COMPOSITE SYSTEM FOR SIMULTANEOUS THERMAL PROTECTION AND ELECTROMAGNETIC INTERFERENCE (EMI) SHIELDING FOR CARBON FIBER REINFORCED POLYMER COMPOSITES (CFRP)
التفاصيل البيبلوغرافية
العنوان:
MULTIFUNCTIONAL CERAMIC COMPOSITE SYSTEM FOR SIMULTANEOUS THERMAL PROTECTION AND ELECTROMAGNETIC INTERFERENCE (EMI) SHIELDING FOR CARBON FIBER REINFORCED POLYMER COMPOSITES (CFRP)
Achieving high electrical conductivity while maintaining good thermal insulation are often contradictory in the material design for the goal of simultaneous thermal protection and electromagnetic interference (EMI) shielding. The reason is that materials with high electrical conductivity often pertain high thermal conductivity. To address this challenge, this study reports a multifunctional ceramic composite system for carbon fiber reinforced polymer (CFRP) composites. The fabricated multifunctional ceramic composite system has a multi-layer structure. The polymer derived SiCN ceramic reinforced with yttria stabilized zirconia fibers serves as the thermal protection and impedance matching layer, while the carbon nanotubes provide the EMI shielding. Thermal conductance of the multi-layered ceramic composite is about 22.5% lower compared to that of the carbon fiber reinforced polymer composites. Thermal insulation test during the steady-state condition shows that the hybrid composite can be used up to 300oC while keeping the temperature reaching the surface of carbon fiber reinforced polymer (CFRP) composites at around 167.8oC. Flame test was used to characterize the thermal protection capability under transient condition. The hybrid composite showed a temperature difference of 72.9oC and 280.7oC during the low and high temperature settings, respectively. The average total shielding efficiency per thickness of the fabricated four-layered ceramic composite system was 21.45 dB/mm, which showed high reflection dominant EMI shielding. The average total shielding efficiency per thickness of the eight-layered composite system was 16.57 dB/mm, revealing high absorption dominant EMI shielding. Typical CFRP composites reveal reflection dominant EMI shielding. Results of this study showed that materials with good thermal insulation and EMI shielding can be obtained simultaneously by confining the electron movement inside the materials and refraining their movement at the skin surface.
