Page 145 - MSAM-4-3

Materials Science in Additive Manufacturing Sunflower-inspired microwave-absorbing metastructure

Table 2. Comparison of microwave absorption performance parameters between the sunflower‑inspired metastructure and
previously reported biomimetic microwave absorbers
Material Structure Thickness (mm) Absorption bandwidth (GHz) References
ABS Bio-inspired gyroid 15 2.3 – 40 22
PEEK/FCIPs Bamboo 15 3.2 – 40 17
Resistance patch+PLA Honeycomb 15.51 3.53 – 24 19
Graphite powder/epoxy resin Bio-inspired moth eye 20 5 – 18 23
CB-CIP/PLA Sunflower-inspired metastructure 10 5.87 – 18 This study
Abbreviations: ABS: Acrylonitrile butadiene styrene; CB-CIP/PLA: Carbon black-carbonyl iron powder/polylactic acid; PEEK/FCIPs: Polyether ether
ketone/flaky carbonyl iron powder.

was successfully fabricated using FDM 3D printing.
Experimental results confirmed that the metastructure
achieves an EAB of 12.13 GHz (5.87 – 18 GHz), with
absorption rates exceeding 90% (RL < −10 dB), effectively
covering the C, X, and Ku frequency bands.
In the CB-CIP/PLA composites used in this study, the
interfacial polarization between CB and CIP improves the
dielectric loss, while natural resonance enhances magnetic loss.
These synergistic effects contribute to the efficient microwave
attenuation observed. In addition, the metastructure absorber
exhibits stable, wide-angle performance: for both TE and TM
polarization states, the absorption bandwidths exceeding 10
GHz are maintained at incident angles up to 50°. Electric and
magnetic field simulations, along with power loss density
distributions, further confirmed the absorption mechanisms
across different frequency bands, namely, λ/4 resonance at low
Figure 14. Comparison of simulated and experimentally measured frequencies, inter-layer structural resonance at intermediate
reflection loss for the sunflower-inspired metastructure, demonstrating frequencies, and edge diffraction at high frequencies. The
the consistency between simulation and measurement results
findings demonstrate that combining biological inspiration
with additive manufacturing offers a promising route for
previously reported biomimetic absorbers. The present developing lightweight, efficient, and broadband microwave-
design achieves competitive absorption performance absorbing materials.
while maintaining a thinner profile. Compared to other
structures, this metastructure benefits from reduced Acknowledgments
thickness and optimized material selection, demonstrating
significant advantages in practical application. Finally, the None.
metastructure is based on a periodic array of identical Funding
unit cells, which can be readily expanded or reduced to
accommodate different application requirements. This study was funded by the Fuzhou–Xiamen–Quanzhou
National Independent Innovation Demonstration
4. Conclusion Zone Collaborative Innovation Platform Project
This work presents a bio-inspired metastructure based (3502ZCQXT2024003) and the Fujian Province Industry–
on the spiral geometry of sunflower seed arrangements, University Cooperation Plan (2023H6015).
developed for broadband microwave absorption. The Conflicts of interest
metastructure integrates a CB-CIP/PLA composite and
a multi-layered spiral gradient configuration to achieve The authors declare they have no competing interests.
both structural simplicity and enhanced electromagnetic
performance. By optimizing structural parameters, Author’s contributions
particularly the gradient impedance increments between Conceptualization: Fei Wang, Kaiyong Jiang, Peifeng Li
adjacent layers, a low-cost metastructure absorber Formal analysis: Pengfei Fang, Zhe Zhang

Volume 4 Issue 3 (2025) 11 doi: 10.36922/MSAM025220048