LIGHTNING PROTECTIVE COATINGS FOR BORON AND GRAPHITE FIBER REINFORCED PLASTICS

Coatings and thin conductive overlays for protecting boron fiber reinforced plastics and graphite fiber reinforced plastics from structural damage by simulated lightning strikes were investigated. Laboratory tests were made in which test panels, with and without coatings, were exposed to currents as high as 200,000 amperes. The greatest protection of the panels from damage, combined with minimum coating weight, was achieved with aluminum wire fabric and aluminum foil overlays. Other protective coatings which had merit were: plasma sprayed aluminum; conductive paints used with aluminum foil strips; and conductive coatings applied over high dielectric strength plastic films.