High-Performance FeSiBNbCu Nanocrystalline Magnetic Powder Cores with Novel Nano-Cr2O3/Epoxy Insulation Layer

In the present work, the thermal stability, insulation performance, and magnetic properties of nanocrystalline soft magnetic powder cores (NSMCs) have been greatly improved, thanks to the successful creation of composite materials that combine inorganic nano-Cr 2 O 3 with organic epoxy resins. By coating the nano-Cr 2 O 3 /epoxy insulating layer on the FeSiBNbCu nanocrystalline powders, the core loss ( P cv ) of the FeSiBNbCu NSMCs is successfully decreased and the DC-bias performance is significantly enhanced. When the content of nano-Cr 2 O 3 is 0.3 wt.%, the FeSiBNbCu NSMCs demonstrate optimal comprehensive soft magnetic properties, including low P cv of 106.2 mW/cm 3 at 100 kHz/50 mT, high effective permeability ( μ e ) of 53.6 at the frequency of 1 MHz and DC-bias characteristics of 62% at a bias field of 100 Oe. As the coating layer of the NSMCs, the nano-Cr 2 O 3 /epoxy composite material has a straightforward, practical, and affordable production process. It is also more suited for industrialization and has a wide range of potential industrial applications.