Preparation And Absorbing Properties Of Ti Oped Barium Ferrite With Multiple Resonance Characteristics

Electromagnetic interference has been a serious problem due to the explosive growth in the utilization of electrical and electronic devices. Absorbing materials have been widely used and absorbing researches have been paid more attentions. Many studies about ferrites because of their large anisotropy field, high saturation magnetization, and excellent chemical stability. Most researches focus on the frequency of2-18GHz in which absorption rate is below-10dB.But frequency range higher than18GHz is less involved.Usually ferrite materials have been improved performance by modifing, such as by ion doping to adjust the magnetocrystalline anisotropy field, or, by mixing materials of different properties. In this paper, M-type barium ferrites BaTinFe12-nO19(n=0.2-1.0) which has different absorbing frequency characteristics were mixed to achieve multiple absorbing frequencys coexisting in a system. In other words, different absorbing peaks of single BTFO coexisted in composite system to widen the bandwidth.The target which multiple resonance absorption corresponded multiple natural resonant frequency could be found in the composite system to improve the absorbing properties can achieve by controlling the material composition, ratio, thickness and so on.M-type barium ferrite composite system xBaTinFe12-nO19+(1-x)BaTimFe12-mO19with multiple resonance characteristics were synthesize by the homologous barium ferrite BaTinFe12-nO19prepared by sol-gel method. Phase structures and morphology were analyzed by XRD and SEM separately. Absorbing properties were analyzed by the vector network analyzer (Agilent E8363C). Result shows that, the absorbing properties of composite system BaTinFe12-nO19+BaTimFe12-mO19series have been prepared successfully, in which n=0.2～0.6, m=0.4～1.0, m≠n.By controlling different component of Ti doped barium ferrite in the same system, this paper makes resonance loss peak under the influence of different intrinsic parameters appear independently in different frequencies.By controlling the different ratio of the same component multiple phase powder this paper can adjust the resonance absorption peak intensity, to homogenize multi-point frequency resonance absorption peak under the case of multiple frequency broadband resonance absorption in similar bandwidth.The absorbing properties of composite system BaTinFe12-nO19 (n=0.8)+BaTimFe12-mO19(m=0.2,0.4,0.6,1.0) series had three resonance loss peak. When system was composed of0.7BaTi0.8Fe11.2019+0.3BaTio.4Fe11.6019,its loss peaks distributed in the R wave Uniformly, whose wave intensities were corresponding-19.0,-17.65and-19.01dB in28.6,33.0and38.7GHz respectively And absorption frequency bandwidth of x BaTio.8Fe11.2O19+(1-x) BaTio.4Fe11.6O19(x=0.7) was12.15GHz.