Effect of the particle size classification of FeSiCrB amorphous soft magnetic composites to improve magnetic properties of power inductors

Abstract

Particle size classification is a key challenge in enhancing permeability and reducing core loss in power inductors used in electronics. In this study, we investigated how the magnetic properties of FeSiCrB amorphous powders are affected by particle sizes. FeSiCrB amorphous powders, which were categorized into five particle size groups labeled S1 to S5 (63–90 μm, 45–63 μm, 32–45 μm, 25–32 μm, ≤25 μm, in that order). XRD patterns show that S1, which encompasses the largest particles, consists of a crystalline phase; all other samples (S2-S5) are shown to have an amorphous phase. Furthermore, the hysteresis loss and eddy current loss of the S5 sample with the smallest particle size were 41.0 kW/m3 and 114.5 kW/m3, respectively, which decreased by 79.5% and 50.5% compared to the S2, showing the optimal core losses. Consequently, it is essential to classify the particle size to obtain the ideal magnetic properties of FeSiCrB amorphous powder.