Fabrication and soft magnetic properties of FeSiB based flakes with insulating surface layer suitable for high frequency power applications

FeSiB based soft magnetic flakes (SMFs; ϕ: 63-106 µm, t: 2-5 µm) coated with optimally thick (∼10 nm) SiO2 were fabricated as the potential material for pressed cores suitable use in power inductors operating beyond 10 MHz. Such thin SMFs produced by mechanical ball milling of commercially available (∼27 ribbons followed an optimized sol-gel coating presence a silane coupling agent. Milling helped to reduce ribbon thickness below skin depth minimize eddy current loss at high frequencies. The effect (medium, duration, rotation speed, and ball-to-powder ratio) conditions on properties investigated. An tiny fraction milled was allowed become nanocrystalline, which augments saturation flux density (BS) permeability (µ) without incurring additional losses. results from X-Ray photoelectron spectroscopy magnetization measurement confirm that stress-releasing post-annealing process reduced coercivity ∼62 Oe ∼6 enhanced moment 126 emu/g 142 affecting yet robust insulating layer.