| Popis: |
In this study, nanocrystalline Ni0.64Zn0.36Fe2O4 powders were prepared by high energy ball milling of ZnO, NiO and Fe2O3 powder mixtures. The synthesized powders were heat treated at different temperatures varying from 400 °C to 750 °C. Structural properties of the as-milled and the post-heat treated powders were studied by means of X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The magnetic properties were measured using a vibrating sample magnetometer (VSM). The results indicate that the crystallite size increases and lattice strain decreases with the increase of annealing temperature. It is also found that the saturation magnetization rises significantly from 17.92 emu/g to 77.04 emu/g as temperature increases from room temperature to 750 °C. In contrast, coercivity has some fluctuation during the heat treatment which can be attributed to the modified random anisotropy models and classic model. |
Full Text from ScienceDirect