Synthesis, Microstruture and Electromagnetic Performance of Ni_xZn_1-xFe₂O₄ Ferrites with Different Ni/Zn Ratios Prepared by a Novel Molten Salt Method

Ni_xZn_1-xFe₂O₄ ferrites (x=0.0∼1.0 with a step of 0.1) were prepared by a novel molten salt method. The effects of Ni/Zn ratio on the microstructure and electromagnetic performance of the acquired ferrites were investigated. All the samples are composed of a pure ferrite with cubic spinel structure, and their microstructures are quite homogeneous. With the increase of Ni content, the lattice constant of the samples decreases, the grain size fluctuates in a very narrow range around 2.0 μm, and the saturation magnetization firstly increases and then decreases, presenting the maximum value with x=0.6, while the coercivity basically displays an inverse trend to the saturation magnetization. In the frequency range from 1 M to 1 GHz, the initial permeability of the acquired Ni_xZn_1-xFe₂O₄ ferrites decreases, the cut-off frequency increases, and the magnetic loss decreases with increasing Ni content. (paper)