Core-shell structured FeSiAl/SiO2 particles and Fe3Si/Al2O3 soft magnetic composite cores with tunable insulating layer thicknesses

- FeSiAl/SiO2 core-shell particles and Fe3Si/Al2O3 composite cores were prepared.
- SiO2 surrounding FeSiAl were replaced by Al2O3 during sintering process.
- Fe3Si particles were separated by Al2O3 with tunable thickness in composite cores.
- Fe3Si/Al2O3 had lower core loss and better frequency stability than FeSiAl core.
- The insulating layer between ferromagnetic particles can reduce core loss.