Composition dependence of microstructure, magnetic and microwave properties in ball-milled FeSiB nanocrystalline flakes

The soft magnetic nanocrystalline/amorphous FeSiB flakes were fabricated by the ball-milling method and evaluations were made of the composition, microstructure, magnetic and microwave properties in the milling process. An investigation of the relationship between microstructure and magnetic/microwave properties showed that the electromagnetic characteristics were attributed to the changes of nanograin size, crystal and amorphous content corresponding to the composition variation. The replacing of Fe atoms by Si in α-Fe crystal caused the decrease of grain size, saturation magnetization and coercivity, while B content devoted to amorphous phase and decreased the permittivity. Consequently, it was observed that the optimum composition for microwave performance is Fe82Si5B13.