Improved permeability and decreased core loss of iron-based soft magnetic composites with YIG ferrite insulating layer

Abstract

In this study, single-phase yttrium iron garnet (YIG) ferrite was synthesized by sol-gel method, which was firstly used as the insulating layer to prepare Fe/YIG soft magnetic composites (SMCs). It was demonstrated that the Fe powders were uniformly coated with the YIG ferrite for the Fe/YIG SMCs. The influence of the YIG content on the soft magnetic properties of the Fe/YIG SMCs were investigated in detail, the results showed that the total core loss (Pcv) of all Fe/YIG SMCs were smaller than pure Fe. The Pcv firstly decreased with increase of the YIG content up to 1.0 wt% (Pcv=2460 mW/cm3, 4 mT/590 kHz), then increased with the increase of YIG from 1.0 wt% to 5.0 wt%. What’s more, the effective permeability (μe) of the Fe/YIG SMCs with YIG from 1.0 wt% to 3.0 wt% were higher than that of Fe, confirming both decreased core loss and improved permeability were accomplished in the Fe/YIG SMCs, which demonstrated that the YIG ferrite has good application prospects as new coating layer for SMCs used in medium to high frequency environments.