Microwave-absorbing properties of La0.8Sr0.2Mn0.86Fe0.14-xCoxO3

作者：Bei, Cheng-Xun^*; Wang, Da; Yao, Ruo-He; Li, Bin

来源：Journal of South China University of Technology(Natural Science Edition), 2009, 37(3): 43-46.

• Complex permeability
• Complex permittivity
• Complex permittivity and permeabilities
• Electromagnetic parameters
• Microwave absorbing materials
• Microwave absorbing properties
• Microwave reflectivity
• Vector network analyzers

La0.8Sr0.2Mn0.86 Fe0.14-xCoxO3=0.01, 0.02, 0.03) crystal powders were synthesized via the sol-gel method, and the crystal structure of the product was characterized by means of XRD. Then, the complex permittivity and permeability of the product in the frequency range of 2-18 GHz were measured using a microwave vector network analyzer. Moreover, the curves describing the relationship between the microwave reflectivity and the frequency were obtained according to the measured data. The results show that, with a thickness of 1.80 mm, La0.8Sr0.2Mn0.86 Fe0.13Co0.01O3 is of an absorption peak height of 27.9 dB and an absorption bandwidth in 2-18 GHz of 5.3 GHz, while with a thickness of 2.00 mm, the height decreases to 26 dB and the bandwidth to 4.9 GHz. According to the tangents of both electric loss and magnetic loss angles, the microwave absorption attributes to both the dielectric and the magnetic loss, especially the former. It is also indicated that the doping of Fe and Co changes the double-exchange of Mn3+-O-Mn4+ system and the electromagnetic parameters of the material, thus improving the microwave-absorbing properties.

• 出版日期2009-3
• 单位华南理工大学