Study on FDM preparation and properties of Fe/PLA/TPU for microwave absorption

As radar technology advances, the demands on electromagnetic stealth capabilities continue to increase. Therefore, developing broadband, high-absorption materials is crucial for fabricating effective wave-absorbing structures. This work fabricated Fe/Polylactic Acid/Thermoplastic Polyurethane (Fe/PLA/TPU) composite filaments and coaxial rings using fused deposition modeling (FDM) technology. The experimental data reveal that as the Fe content rises, the dispersed particles progressively form a continuous network within the matrix. This structural evolution enhances interfacial polarization effects, substantially boosting the composite's microwave absorption performance. Specifically, the developed material achieves an impressive absorption bandwidth (EAB) of 6.56 GHz (10.14-16.9 GHz) with a maximum reflection loss (RL) of -69.48 dB at merely 2 mm thickness. Additionally, the tensile and bending strengths of the composites were 14.9 MPa and 9.8 MPa, respectively. This research result provides effective support for the application of electromagnetic stealth technology.