Modulation effect of Zr-Sm co-doped on microwave absorption performance of barium ferrite

Abstract

Zr-Sm co-doped barium ferrites BaFe12–2x(ZrSm)xO19(x = 0, 0.2, 0.4, 0.6) were successfully prepared by sol-gel method. The effects of Zr-Sm co-doped on phase formation, microscopic morphology, magnetic parameters, electromagnetic and microwave absorption properties of barium ferrite were studied. The results show that the saturation magnetization(Ms) of BaFe12–2x(ZrSm)xO19 first increases and then decreases, the coercivity(Hc) first decreases and then increases with the increase of doping amount(x) of Zr-Sm. Large grain size and sheet morphology lead to the transition of BaFe11.6(ZrSm)0.2O19 towards soft magnetic properties. The introduction of Zr-Sm increases the amount of oxygen vacancies, and dielectric loss value of material is obviously enhanced, this improves the polarization relaxation of materials. At the same time, multiple natural resonance peaks appeared in the virtual part of the permeability (μ"), which regulated the absorbing properties of samples. The best microwave absorption properties of sample is obtained when doping x = 0.2, at the thickness of 2.8 mm, the maximum reflection loss(RL) is − 51.75 dB. The effective absorption bandwidth (RL ≤ −10 dB) is 4.4 GHz, it covers almost all the X-band(8–12 GHz). Compared with existing doped barium ferrite, the material possesses a greater reflection loss and excellent prospects in the field of microwave absorption.