Mechanical and electromagnetic absorption study on polyaniline and graphene oxide filled epoxy reinforced with graphite‐carbon plate composites for stealth application

Abstract This research focuses on understanding of polymer composites' ability to absorb Radio frequency waves for stealth application, specifically for evading radar detection. The composites were developed using a Carbon‐Graphite base plate layered with carbon fiber mat on both sides reinforced in a polyaniline (PANI) and Graphene oxide (GO) mixed Epoxy matrix with added triethylamine (TEA). Four samples with different volume percentage were fabricated, having same Epoxy of 52%, Hardener of 26% and PANI of 10%, but different volume percentages of GO and TEA. The fabricated composites are named as EPCG‐1 (4% GO and 8% TEA), EPCG‐2 (5% GO and 7% TEA, no Carbon fiber), EPCG‐3 (5% GO and 7% TEA) and EPCG‐4 (7% GO and 5% TEA). The developed composites were characterized by subjecting to tensile testing, Scanning Electron Microscopy analysis, Ultraviolet–visible spectroscopy, Fourier Transform Infrared spectroscopy, Impedance spectroscopy and Directional Coupler test. The EPCG‐4 composites achieve a highest tensile strength of 45.61 N/mm 2 and highest absorbance of 1.574 AU corresponding to a wavelength of 875.00 nanometers. The microwave absorbing capacity was evaluated in terms of absorption, reflection and transmission, where the highest shielding efficiency of 32.76 is observed in EPCG‐4 composite when tested in X‐band frequency range (8–12 GHz). Infrared indicated the stretching of bonds like CN and CH due to addition of graphene oxide. The permittivity of the composite is higher for EPCG‐4 composite. Compared to all the tested composites, EPCG‐4 exhibits better mechanical and stealth properties. Highlights Development of electromagnetic absorbing composites material for stealth application. Conductive composites of Graphite‐Carbon plate, layered with Carbon fiber mat bonded by PANI and GO mixed Epoxy matrix are prepared. Analyzing radio‐frequency absorption, reflection and transmission of the composites using wave guide method. UV–vis spectroscopy analysis the wave absorbing capacity of stealth composites. Microscopic analysis on stealth composite to understand the conducting fillers distribution.