Study on FeSiAl magnetic powder core coated with nano-Y2O3 and its influence on magnetic properties

The microstructure and magnetic properties of the FeSiAl /phosphoric acid/nano-Y2O3/kaolin soft magnetic composites were investigated in this article. The morphology and structure were characterized by SEM, EDS, XRD, DSC, and XPS. The surface of FeSiAl powder particles was densely and uniformly coated with a phosphoric acid/nano-Y2O3/kaolin insulating coating. It was discovered that nano-Y2O3 played a dominant role in the coating process. Using a precision magnetic analyzer and lossy power tester, the effective permeability, quality factor, DC bias performance, and the core loss of the FeSiAl/phosphoric acid/nano-Y2O3/kaolin SMCs after pressing and annealing were computed and examined. The results show that nano-Y2O3 can improve the quality factor and DC bias performance of the powder core, but leads to a reduction in magnetic permeability and the core loss is also a little high. This behavior may be caused by the competition mechanism: nano-Y2O3 lowers the magnetic coupling between FeSiAl particles, resulting in a decrease in permeability and an increase in the core loss. When the content of nano-Y2O3 is 5 wt%, the comprehensive magnetoelectric performance is good (ue=21.04, at f =100 kHz; Pcv = 1555.13 mW/cm3, at f = 50 kHz; Q = 150.25, at f = 70 kHz; at Bm = 1000 Gs). The effects of nano-Y2O3 coating on the permeability and the loss of FeSiAl SMCs will be a major focus of future research and development.