Amorphous soft magnetic composite-cores with various orientations of the powder-flakes

•The powders can be orientated to form ordered structure along the magnetic lines.•Circular orientation of the powders improves soft magnetic properties of cores.•Reduction of the demagnetizing field within the powders can increase the µe.•Structural ordering can be used for optimal design of magnetic composite materials.

Fe78Si9B13 amorphous powder cores were prepared by cold pressing the amorphous powders crushed from amorphous ribbons and orientated with an external magnetic field. Three orientations of magnetic powder cores were obtained: (i) the disorderedly orientated amorphous magnetic powder core (DOAMP), (ii) the circularly orientated amorphous magnetic powder core (COAMP), and (iii) the radially orientated amorphous magnetic powder core (ROAMP). The effect of the shape anisotropy of the flake powders on the magnetic properties of the powder cores was investigated. The powders parallel to external magnetic field is beneficial for achieving the excellent performance of the cores. Below 100 kHz the product of the effective permeability and the quality factor of COAMP core increases by 9.1% and 21.2% compared to that of the DOAMP and the ROAMP cores, respectively, while the coercive field and the magnetic induction intensity keep almost the same. Pressing magnetic powders under a magnetic field to form preferred orientation is suitable for optimal design of soft magnetic cores toward practical applications.