Polymer Composite Conductors and Lightning Damage

With the improvement of aircraft design and the advancement of carbon fiber reinforced polymer (CFRP) composite manufacturing and design technologies, the proportion of CFRP in commercial aircraft, military aircraft, unmanned aircraft, and stealth aircraft continues to increase due to its superior mechanical strength, low density, high durability, and excellent workability. However, compared with traditional metallic materials, the large amounts of charge associated with a lightning strike process cannot be transferred and dissipated effectively in CFRP materials. The accumulated Joule heat causes a sharp increase in local temperature of the CFRP laminates and leads to serious damage, such as fiber sublimation, resin pyrolysis, and deep delamination. The poor lightning strike tolerance of CFRP has become a technical bottleneck restricting the wide application of CFRP materials in the aerospace‐manufacturing industry. In this chapter, the conductive characteristics, especially the dynamic characteristics, of CFRP under lightning current impulses were investigated and analyzed. Then the experimental research and computational simulation for lightning damage properties of CFRPs were studied, and the influence of dynamic conductance on lightning damage of CFRP was analyzed. The experimental study on lightning damage of CFRPs subjected to single and multiple lightning components was conducted, and the correlation between lightning damage of CFRP and the waveform parameters of lightning current impulses was obtained. The coupled thermoelectrical model based on the dynamic conductive properties of CFRP was established to simulate the thermal damage effect of CFRP under lightning current. The simulation results and the experimental investigation of the internal damage behavior of CFRP provide a further understanding of the lightning current interaction mechanism on CFRP.