In the present study, we address the combined response of iron (Fe) and nickel (Ni) metal powders on the microwave absorption properties of nanographite (NG) particles in the 8–18 GHz frequency band. NG was synthesized from graphite via high-energy planetary ball mill (wet milling). Similarly, hybrid Fe-Ni-NG particles in two individual (25:25:50 and 37.5:37.5:25) ratios were synthesized and characterized for studying their structural and morphological properties. Further, the samples were dispersed in epoxy-based aero-grade paints to analyze their particle size and rheological properties. Thus, produced nanocomposite paints were coated on aluminum sheets for analyzing their functional properties including impedance measurement and microwaves absorbency measurements. The hybrid nanoparticle coatings exhibited a reflection loss of − 21 dB for 25:25:50 (Fe-Ni-NG) sample at 18 GHz and nearly − 18 dB for 37.5:37.5:25 (Fe-Ni-NG) sample for a wider frequency range from 14 to 18 GHz with a coating thickness of 1.8 mm. These advanced nanoparticles can be used for the development of flexible coatings in various defense applications including stealth aircrafts and low observable technologies in the future.