Soft magnetic properties of FeSiAl/carbonyl iron composites with high magnetic permeability and low magnetic loss

Highlights: • With the increase of carbonyl iron content, the magnetic permeability of the composites increased. • FeSiAl/carbonyl iron composites have higher saturation magnetization and low power losses. • Hysteresis loss is below the commercial value, which may have commercial application value in high-power electrical systems. -- Abstract: FeSiAl/carbonyl iron composites with high magnetic permeability and low magnetic loss was prepared. The microstructure and magnetic properties of the sample were studied by using XRD, SEM, EDS, XPS and superconducting quantum interference device (SQUID Quantum Design MPMS-3) magnetic property measurement system. It is found that with increase of carbonyl iron content, magnetic permeability of the composites increased, and magnetic loss first decreased and then increased. This manifestation may be produced by a competitive mechanism: the presence of carbonyl iron particles strengthens the magnetic coupling among FeSiAl particles, which leads to an increase in magnetic permeability and reduces hysteresis loss; on the other hand, the hysteresis loss of carbonyl iron itself is greater than that of FeSiAl. The composite has the lowest magnetic loss and highest magnetic permeability when the carbonyl iron content is 4%, which may have commercial application value in high-power electrical systems.