Abstract
Polycrystalline Ba3Co2Fe24O41 specimens were fabricated by usual solid state sintering or spark plasma sintering method. SEM observation showed that densification occurred simultaneously with grain growth in the solid state sintering. The spark plasma sintering produced dense ceramics with fine grain structure. Their complex permeability spectra were evaluated with a help of numerical calculation based on our previous model, which is related to the microstructure. Both spin rotation and domain wall motion affected the permeability in the solid state sintered specimens. The permeability of the spark plasma sintered specimens was mainly attributed to spin rotation.
