An investigation of the titanium effect on the structural and magnetic properties of BaNi2 based W-type hexaferrites

The polycrystalline samples of the composition Ba(Ni1−xTix)2Fe16O27 were prepared by the conventional ceramic method with (x = 0.0–1.0). Effects of titanium (Ti) doping on structural and magnetic properties of BaNi2 based W-type hexaferrites were analyzed. The samples were initially sintered in air at 1000 °C for 4 h and finally at 1300 °C for 9 h. The X-ray diffraction patterns confirm the presence of single W-hexagonal phase. The lattice parameters ‘a’ and ‘c’ were found to show irregular behavior by increasing Ti content. The variations of magnetic properties were observed by analyzing hysteresis loop of prepared samples. The results show that maximum magnetization (M) and remanence (Mr) decrease up to x ≤ 0.6 due to replacement of Ti ions for spin down (4f2) and spin up (12k, 2a and 2b) sublattices, but a substantial increase of M and Mr for (x = 0.8 and1.0) could be attributed to the replacement of Ti ions for spin down sublattices (4f2). The coercivity (Hc) was found to decrease with increasing Ti content. An increase of grain size with Ti content was also observed. Since, Hc is inversely proportional to the packing fraction of magnetic materials or the grain size.