Abstract: The rational modulation of the heterogeneous components of magnetic carbon-based composites has become an effective strategy to improve their electromagnetic wave (EMW) absorption properties. In this work, a series of Fe_0.64Ni_0.36-carbon nanotubes (CNTs)/Carbon foam hybrid composites with different ratios has been prepared by a simple loading and calcination process. The results indicate that Fe_0.64Ni_0.36 alloy nanoparticles, obtained via in-situ carbon reduction of NiFe₂O₄ prepared by nitrate thermal decomposition, are uniformly dispersed within the interwoven network of CNTs and the carbon skeleton. The three-dimensional conductive network formed by CNTs and foam provides conductive loss that optimizes impedance matching, while the layered interfaces between the multiple components enhance polarization loss, and the Fe_0.64Ni_0.36 alloy nanoparticles promote magnetic loss. Notably, the sample with CNTs additions of 40 mg (FN-40CNT/CF) exhibits desirable EMW absorption properties, including optimum reflection loss (RL_min) of -97.65 dB at a thickness of 1.4 mm and the widest effective absorption bandwidth (RL ≤ -10 dB) of 11.28 GHz at 1.8 mm. Furthermore, the radar cross-section values of FN-40CNT/CF are less than -10 dB m² across detection angles, effectively reducing the probability of the target detected by the radar. Therefore, Fe_0.64Ni_0.36- CNTs/Carbon foam hybrid composites have potential application value and broad prospects in areas such as radar stealth and EMW absorption.

Key words: Carbon foam, Fe_0.64Ni_0.36 alloy, Electromagnetic wave absorption, Bandwidth