Study on phase, structural changes and microwave absorption of magnetic powder with BaZn0.6Zr0.3X0.3Fe10.8O19 (X=Ti,Ce,Sn) composition

In this research, barium hexaferrite samples with BaZn0.6Zr0.3X0.3Fe10.8O19 (X=Ti,Ce,Sn) composition were synthesized via mechanical activation method and were evaluated by X-ray diffraction (XRD), field emission electron microscopy (FE-SEM), vibrating sample magnetometer (VSM) and Vector network analysis (VNA). X-ray diffraction results confirmed the present of barium hexaferrite as a dominant phase with small amount of hematite as a non-magnetic phase in the sample compound. Lattice parameters a and c was increased due to the difference between ionic radius of guest and host ions and the largest increases was related to the sample that containing cerium ion. The FE-SEM results confirmed the average particles size of about 450 nm and 250 nm for samples without and with dopant respectively. According to M-H curves the value of saturation magnetization (Ms) and coercive force (Hc) was reduced in all cases and significant changes were observed in magnetic properties of barium hexaferrite with the effect of substitution of Fe ions. According to the results maximum magnetic saturation (33.1 emu/g) and minimum coercivity force (8.14 Oe) were related to samples with composition of BaZn0.6Zr0.3Ti0.3Fe10.8O19 and BaZn0.6Zr0.3Sn0.3Fe10.8O19 respectively. According to the results of microwave absorption in the frequency range of 8-12.4 GHz the maximum absorption was related to the sample with the composition of BaZn0.6Zr0.3Sn0.3Fe10.8O19 at the frequency of 11.1 GHz was -16.3 dB.