Rare earth substituted M-type lead hexaferrite: synthesis, electrical and magnetic properties

In this article, the synthesis and the electrical and magnetic characterization of the M-type lead hexaferrite were presented. Rare-earth substituted lead hexaferrite was synthesized by the traditional ceramic process. The final product was obtainedby sintering the lead hexaferrite compact at 950ºC for 2 h. According to the XRD analysis, secondary phases did not appearin the patterns. The electrical polarization curve of the sample did not confirm the ferroelectric response. The dielectricconstant vs. frequency indicated a reduction trend. As observed from the polarization curve, the polarization value changedbetween 0.8 and -0.8 μC/cm2 under the voltage of 5.76 kV. The high symmetry of the crystal in this sample is proposed tobe the origin of the absence of ferroelectric response. Vibrating sample magnetometer (VSM) measurements confirmed theferrimagnetic behaviour for both RT and low temperature. The saturation magnetizations (Ms) were found to be 7.54-8.08emu/g in the temperature range of 7-22 K and the highest coercivity value was found to be 1.2 kOe and this result depictsthe magnetically soft nature and multi-domain structure. The results showed that the obtained lead hexaferrite sample hasacceptable magnetic properties.