Investigation of Microwave and Structural Properties of Carbon Veil-Based GFRP Composite for Stealth Applications

In this study, the effect of using carbon-based non-woven fabric (NWF) also known as a veil, on the mechanical and electromagnetic properties of glass/epoxy-based functional composites has been investigated. A fiber spinning technique was used to manufacture Carbon Veil (CV) in which optimized weight percentages of carbon fibers have been infused with glass fiber. Carbon veil with glass fiber-reinforced polymer (CV/GFRP) composites with different stacking sequences have been prepared through the wet-layup process for electromagnetic and mechanical characterization. The electromagnetic properties of the GFRP/Veil composites, along with their complex permittivity and permeability, were investigated using a free space measurement system in the C, X, and Ku bands (5.2–18 GHz). Microwave absorbing properties show that a minimum 10 dB reflection loss (90% electromagnetic absorption) is attained for the CV-based radar-absorbing structure (RAS) composite in the entire C and X frequency region having a composite thickness of 4.5 mm. Mechanical properties of CV/GFRP composites, including tensile strength, flexural strength, and inter-laminar shear strength, were examined using American Society for Testing and Materials (ASTM) standards. The fabricated CV/GFRP composite shows a prospective claim for radar absorption and structural application.

Graphical Abstract