The hierarchical structures of carbonized melamine foam modified by FeNi alloy and silicon layer (CMF/FeNi-SiO₂) have been fabricated by a magnetron sputtering method. The as-prepared CMF/FeNi-SiO₂ composites exhibited a three-dimensional porous structure, with the framework uniformly covered by a FeNi layer with several hundred nanometers and an ultrathin SiO₂ layer, which demonstrated soft magnetic properties at room temperature. Moreover, the microwave absorption performance of the foam was investigated in the frequency range from 2 to 18 GHz. The results showed that the microwave absorption performance of CMF/FeNi-SiO₂ composite was significantly enhanced in the low-frequency range compared with CMF/FeNi. The minimum reflection loss of CMF/FeNi-SiO₂ with an absorption thickness of 4.1 mm was about −53 dB at 3.38 GHz and reached an effective absorption bandwidth of 0.93 GHz (from 2.93 GHz to 3.86 GHz). The frequency bandwidth of 8 GHz (2.35 ~ 6.35 GHz, 8.4 ~ 12.4 GHz) with absorption loss ≤ −10 dB and the frequency bandwidth of 2.05 GHz (2.62 ~ 4.67 GHz) with absorption loss ≤ -20 dB demonstrated the CMF/FeNi-SiO₂ a high-efficient absorber in the low-frequency band (2–6 GHz), which stemmed from improved impedance matching and attenuation capacities.

采用磁控溅射法制备了FeNi合金和硅层(CMF/FeNi-SiO _{2 )改性碳化三聚氰胺泡沫的分层结构。}所制备的CMF/FeNi-SiO ₂复合材料呈现出三维多孔结构，骨架均匀覆盖有数百纳米的FeNi层和超薄SiO ₂层，在室温下表现出软磁性能。此外，还研究了泡沫在 2 至 18 GHz 频率范围内的微波吸收性能。结果表明，CMF/FeNi-SiO _{2的微波吸收性能}与 CMF/FeNi 相比，复合材料在低频范围内显着增强。_{吸收厚度为 4.1 mm 的 CMF/FeNi-SiO 2}在 3.38 GHz 时的最小反射损耗约为 -53 dB，并达到 0.93 GHz 的有效吸收带宽（从 2.93 GHz 到 3.86 GHz）。8 GHz (2.35 ~ 6.35 GHz, 8.4 ~ 12.4 GHz)频率带宽吸收损耗≤-10 dB和2.05 GHz (2.62 ~ 4.67 GHz)频率带宽吸收损耗≤-20 dB证明了CMF/FeNi- SiO ₂是低频段（2-6 GHz）中的一种高效吸收剂，源于改进的阻抗匹配和衰减能力。