Efficient inorganic-coated FeSiAl/WS2 soft magnetic composites with low magnetic loss

In this study, two-dimensional (2D) layered semiconductor material WS2 was used as an insulating agent, and FeSiAl/WS2 soft magnetic composites (SMCs) were prepared by ultrasonically mixing WS2 and atomized FeSiAl in an appropriate mass ratio. The morphology and magnetic properties of the FeSiAl/WS2 composites were systematically studied. Results of scanning electron microscopy showed that 2D layered WS2 was peeled into nano- and micron-sized sheets after ultrasonic treatment. These sheets were evenly coated on the surfaces of the FeSiAl grains to form a high-efficiency inorganic coating layer. Magnetic property tests revealed that the FeSiAl/2.25 wt%WS2 composite had a low eddy current loss and moderate effective permeability. A complex permeability test indicated that WS2 not only improved the relaxation frequency and Q value but also reduced the eddy current loss of the FeSiAl/WS2 composites, making FeSiAl/WS2 composites suitable for high-frequency applications. The magnetic loss of the FeSiAl/2.25 wt%WS2 composite was found to be 431 kW/m3 under Bm= 0.1 T and f= 0.1 MHz, which was nearly 30 % lower than that of commercial FeSiAl SMCs.