Microwave absorption properties of nanostructure composite particles based on SrFe12O19

This paper studies the magnetic and absorption properties of ferrites based on SrFe12O19, which were synthesized by the co-precipitation method. The microstructural, structural, loss, and magnetic properties were measured by X-ray diffractometry, field emission scanning electron spectroscopy, network analysis, and vibrating-sample magnetometry, respectively. For the SrFe12O19/ZnFe2O4, the hysteresis loops showed a decreasing in coercivity from 2.8 kOe to 0.03 kOe by increasing ratio of soft/hard (S/h) and decreasing in saturation magnetization from 0.7 kg to 0.01 kg by increasing it. These effects were also observed for nanostructure composite particles of SrFe12O19/NiFe2O4 except for increasing of saturation magnetization by increasing the S/h. The effects of kind and amount of soft phase on microwave absorption properties were also estimated in the X-band (8 GHz to 12 GHz). The maximum reflection loss of the nanostructure composite particles reached to -30 dB at 9.8 GHz for SrFe12O19/NiFe2O4, making it suitable for application in radar-absorbing materials.