Enhancement of the magnetic properties of Fe-Si-Cr soft magnetic composite by selective oxidation annealing

•The possibility for the insulation of Fe-3Si-5.5Cr powder by the selective oxidation annealing was examined.•Insulation oxide layer was formed on the powder surface by the selective oxidation of Si and Cr.•The withstanding voltage was increased by the formation of oxide layer on the powder.•The magnetic properties such as inductance, permeability, and quality factor were improved by using the selectively oxidized powder.