Eliminating lightning strike damage to carbon fiber composite structures in Zone 2 of aircraft by Ni-coated carbon fiber nonwoven veils

By using standardized Waveforms C and D, this study explored the lightning strike protection (LSP) effectiveness of nickel coated carbon fiber nonwoven veils (Ni-CFNVs) on protecting the carbon fiber composite structures in Zone 2 (aircraft lightning zoning). The post-lightning damage was evaluated by visual inspection, ultrasonic scan and residual strength test. Results showed that the Ni-CFNV of 70 g/m² eliminated lightning strike damage inflicted by both waveforms and it even performed better than the commercial expanded copper foil of 73 g/m². Therefore, the Ni-CFNV will be a promising alternative to metal mesh for eliminating lightning strike damage to the structures in Zone 2. The remarkable LSP effectiveness of Ni-CFNV can be explained by its integration of high electrical conductivity of Ni-coating and prominent ablation resistance of carbon fiber. The experiments indicate that not only the electrical conductivity, but also the ablation resistance of LSP layer greatly influences the LSP effectiveness.