Developing microwave absorbing materials that stably operate under high humidity and salt spray while maintaining durability remains a significant challenge. A novel NiFeSiAl/carbon nanotube array/SiO 2 (NFSA/CNTA/S) composite with dual microwave absorption and anti-corrosion functionalities is developed via a coupled catalytic chemical vapor deposition (CCVD) and sol-gel strategy. Ball-milled NFSA flakes act as both catalyst and magnetic component, while vertically aligned CNTA grown via CCVD enhance dielectric loss and form a conductive network. Magnetic losses from NFSA (hysteresis, eddy current, natural resonance) and dielectric losses from CNTA (conductivity, interface polarization) achieve broadband absorption. SiO 2 coating improves impedance matching and reduces corrosion current to 2.651 × 10 −7 A/cm 2 . The composite reaches a minimum reflection loss (RL min ) of −42.36 dB and effective absorption covering a substantial portion of the X and Ku bands. This coupled CCVD with sol-gel approach provides a pathway for designing novel NFSA/CNTA/SiO 2 hybrids with high-performance microwave absorption and anti-corrosion.
Soft magnetic composites with enhanced permeability and reduced power loss are urgently needed in the next generation of power electronics and electrical machines. However, traditional insulation techniques suffer from the uneven coating or complex process, which cannot meet these requirements. Here, the feasibility of Ba(OH) 2 as a coating layer of soft magnetic powder is explored. Due to its low melting point, Ba(OH) 2 exhibits good flowability in the molten state, enabling it to evenly coat FeSiAl particles and fill interparticle gaps, thereby forming a uniform, dense insulating layer. This novel coating strategy improves the formability of the magnetic powder cores and optimizes the cores’ soft magnetic performance. Compared with SMPCs without Ba(OH) 2 coating, FeSiAl@Ba(OH) 2 SMPCs have higher magnetic permeability (μ e = 59.5), higher quality factor ( Q max = 127.3), lower high-frequency power loss ( P cv = 2062.9 mW/cm 3 @1 MHz and 50 mT), and good DC bias performance. Our results provide a new approach for the design of insulation coatings for SMPCs, demonstrating significant application potential for high-frequency electronic devices.
危险品化学品经营许可证（带存储）