FeSiAl/(Ni_0.5Zn_0.5)Fe₂O₄ magnetic sheet composite with tunable electromagnetic properties for enhancing magnetic field coupling efficiency

Flaky FeSiAl alloy (9.5 wt% Si, 5.5 wt% Al and Fe balance) was prepared by using mechanical milling method. Fine ferrite powders were produced by oxalate co-precipitation process. Flexible composite sheets were fabricated via tape-casting method by mixing the flake-shape sendust and various weight fraction of NiZn ferrite. X-ray diffraction, scanning electron microscopy and vibrating sample magnetometer were used to characterize the samples. Electromagnetic properties measurement results indicated that permittivity, permeability, power loss of flaky FeSiAl/NiZn ferrite composite can be well tuned by adjusting the amount of loading NiZn ferrite particles. It is found that the magnetic field coupling efficiency is enhanced by attaching the composite with the mix of ferrites. Consequently, the composite filled with 14 wt% of ferrite particles showed the best coupling ratio at 1 MHz-1GHz. This research work shows promising results and making FeSiAl/NiZn ferrite composite a potential magnetically conductive material for energy transmission applications, such as NFC. - Highlights: • Flexible SMC was fabricated by combining the FeSiAl flakes with NiZn ferrites. • The loss mechanisms and the combined effect of ferrite and alloy are discussed. • Magnetic field coupling efficiency is enhanced by attaching FeSiAl/NiZn ferrite composites. • The optimal mass fraction of NiZn ferrite has been determined to be 14 wt%.