Effect of microstructure on magnetic properties of Ni–Zn ferrites

Polycrystalline Ni0.34Cu0.12Zn0.56Fe1.98O4 with different grain sizes up to 39 μm was investigated. At the frequency of 50 kHz, both the hysteresis loss under the excitation condition of 150 mT and the initial permeability decreased with increasing grain size. These results were interpreted in terms of the contribution of grain boundaries and pores inside the grains to the domain wall pinning. [Copyright &y& Elsevier]