Investigation of magnetic properties of Ni0.2Cu0.2Zn0.6Fe1.96O4-BaTiO3 composites

Composite materials with a ferromagnetic Ni0.2Cu0.2Zn06Fe1.96O4 phase and a ferroelectric BaTiO3 phase, xBaTiO(3)-(1-x)Ni0.2Cu0.2Zn0.6Fe1.96O4, in which x varies from 0 to 1, have been prepared via standard ceramics method with nanosized precursor powders. With the variation of x, typical magnetic hysteresis loops of composites have been observed in the composites at the room temperature. When the content of ferroelectric BaTiO3 phase increases, the saturation magnetization and initial permeability decrease. Meanwhile, the coercive force tends to increase. Additionally, the cut-off frequency and quality factor of composite materials shift toward higher frequency. The simultaneous presence of nonmagnetic BaTiO3 in composites pinned the domain wall motion, which lead to the decrease of initial permeability and the increase of cut-off frequency. Microstructure observation shows that the composites possess very fine crystalline grains. (C) 2003 Elsevier B.V. All rights reserved.