Cation distribution and magnetic property of Ti/Sn-substituted manganese-zinc ferrites

Manganeseezinc ferrites with the composition of Mn0.782-xZn0.128Mx4+Fe0.09+2x2+Fe2-2x3+O4(x = 0; M = Ti, x = 0.004; M = Sn, x = 0.004) have been prepared by a solid-state reaction method. The cation distribution has been investigated by the Rietveld refinement of X-ray diffraction (XRD) patterns, fracture microstructure by scanning electron microscope (SEM), and magnetic property by LCR and BeH analyzer, respectively. The results show that Ti4+ and Sn4+ ions prefer to occupy octahedron sublattices (B sites), which leads to an increase in lattice parameter. Sn4+ ions substituted MnZn ferrite has much denser and more uniform microstructure with smaller grains than that of Ti4+ ions substituted and unsubstituted MnZn ferrites. The Curie temperature (T-c) of Ti4+ and Sn4+ substituted MnZn ferrites is higher than that of unsubstituted sample. In addition, both Ti4+ and Sn4+ substitutions, due to the compensation of magnetocrystalline anisotropy constant, can move the secondary peak of mu(i) similar to T curve to low temperature. However, the opposite variation trend has been observed in a P-L similar to T curve. Also, the DC-bias superposition characteristics have been discussed. (C) 2015 Elsevier B.V. All rights reserved.