Synthesis of FeNi@kaolin soft magnetic composites with adjustable magnetic properties under different DC bias fields

Constructing the high-quality insulating layer and verifying the effects of DC bias field on magnetic properties is crucial in optimizing magnetic components based on soft magnetic composites. In this paper, a novel APTESinvolved insulation technique has been developed to successfully coat kaolin on FeNi particles. Additionally, magnetic properties can be effectively regulated by changing the dosage of kaolin. The results show that antimagnetization capacity and resistivity are improved by increasing kaolin content. Loss separation model and magnetic field simulation were used to investigate how the coating layer and DC bias field influence core loss for FeNi@kaolin SMCs. It can be found that structural demagnetizing field and eddy current were believed to be the main determinants of core loss variation in ideal sinusoidal waves, while the degree of magnetization state away from saturation plays a leading role in core loss under larger DC bias fields. Therefore, FeNi SMCs insulated with 1 wt% and 7 wt% kaolin exhibit the lowest core loss at DC bias field of 0 Oe and above 100 Oe, respectively. This work not only provides an effective insulating technique, but also supplies deeper insights into optimizing SMCbased magnetic components under larger DC bias fields.

Automated summary

In this study, the construction of a high-quality insulating layer and the effects of a DC bias field on magnetic properties in soft magnetic composites were investigated. A novel insulation technique involving APTES was developed to successfully coat kaolin on FeNi particles, and the magnetic properties were effectively regulated by changing the dosage of kaolin. The results showed that increasing the kaolin content improved the antimagnetization capacity and resistivity. The study used a loss separation model and magnetic field simulation to investigate the influence of the coating layer and DC bias field on core loss for FeNi@kaolin SMCs. The results indicated that the structural demagnetizing field and eddy current were the main determinants of core loss variation in ideal sinusoidal waves, whereas the degree of magnetization state away from saturation played a leading role in core loss under larger DC bias fields. FeNi SMCs insulated with 1 wt% and 7 wt% kaolin exhibited the lowest core loss at a DC bias field of 0 Oe and above 100 Oe, respectively. This work not only provides an effective insulating technique but also offers deeper insights into optimizing SMC-based magnetic components under larger DC bias fields.