Response of electroless copper coated CFRP laminates to emulated lightning strikes

Lightning strike emulator was employed for evaluating the response of copper electroless coatings on epoxy-CFRP laminates under these high demanding electrical events. Samples were coated for 15 and 30 min producing 0.6 and 1.2 mu m thick layers, respectively, and their performances were compared with commercially protected and naked laminates. Data show that a thin copper layer can improve the performance of CFRP under 40 kA discharges by absorbing part of the electrical energy, as a sacrificial protection. The surface of delaminated composite was lower whereas the coating area affected was larger for samples treated at longer times. An interesting relationship was found between the charge transfer and the damaged area, for all samples. In addition, sustained 30 A injection tests were performed and both electrical data and thermal imaging showed a better tolerance to continuous currents and a better heat dissipation of 30 min versus 15 min coated samples.

Automated summary

The study found that coating carbon fiber reinforced composites with a thin copper layer can improve their performance under high current by serving as sacrificial protection. Samples treated for longer times had larger affected coating areas and lower surface delamination in the composite materials. An interesting relationship was found between charge transfer and damaged areas among all samples.