Improvement of Bonding Characteristics Between the Frequency Selective Surface and E-Glass/Epoxy Composites for Stealth Radomes

Radomes of weapon systems such as aircraft, warships, and missiles have been manufactured using FSS (Frequency Selective Surface) for the stealth performance and E-glass/epoxy composite to protect the radar antenna from weather and mechanical impact and to minimize the loss of EM (electromagnetic) waves transmitted through the radome. In this work, the FSS was manufactured from an FCCL (Flexible Copper Clad Laminate) composed of a copper foil of 20 μm thickness and a polyimide film of 40 μm thickness. The bonding characteristics between the FSS and E-glass/epoxy composite were determined for different surface treatments of copper such as atmospheric pressure plasma treatment and nitric acid/ferric chloride treatment. The EM transmission characteristics of the FSS were also measured by the free space measurement system before and after surface treatments. Nitric acid/ferric chloride treatment of the FSS was found to be a promising method to enhance the bonding characteristics between the FSS and the E-glass/epoxy composite without change in the EM transmission characteristics of FSS.