Magnetic, dielectric and microwave properties of the BaFe12-xGaxO19 (x ≤ 1.2) solid solutions at room temperature

The BaFe12-xGaxO19 (x = 0.1-1.2) solid solutions of the barium hexagonal ferrite of M-type were synthesized and attested by the powder X-ray diffraction method at 300 K. The unit cell parameters were refined. With increase of substitution level the parameters of unit cell monotonically decrease. These samples were investigated by the vibration magnetometry method. With increase of substitution level the magnetic parameters monotonically decrease. The concentration dependence of the TC Curie temperature as well as the MS spontaneous specific magnetization and the HC coercive force at 300 K is constructed. The microwave properties of the considered samples in the external magnetic bias field were also investigated at 300 K. It is shown that with increase of Ga3+ concentration from x = 0.1 to x = 0.6 the frequency value of the natural ferromagnetic resonance decreases in the beginning, and at further increase in concentration up to x = 1.2 it increases again. With increase in Ga3+ concentration the line width of the natural ferromagnetic resonance increases that indicates the increase of frequency range where there is an intensive absorption of electromagnetic radiation. At the same time the peak amplitude of the resonant curve changes slightly. The frequency shift of the natural ferromagnetic resonance in the external magnetic bias field takes place more intensively for the samples with small Ga3+ concentration. It is shown the prospects of use of the Ga-substituted barium hexagonal ferrite as the material effectively absorbing the high-frequency electromagnetic radiation. (C) 2017 Elsevier B.V. All rights reserved.