Preparation and electromagnetic wave absorption properties of M-type barium ferrite

Hexagonal barium ferrite powders were prepared by sol-gel auto-combustion method in order to research the microwave absorption properties of M-type ferrite. The crystal structure,decompounding process, micrograph and microwave absorption properties of the sample were studied by means of XRD,TG-DTA, SEM and vector network analyzer. According to the transmission line theory,the reflection loss of electromagnetic radiation was calculated and the optimum thickness was predicted. The study shows that the prepared sample is found to be M-type barium ferrite with single phase. The optimum thickness is 0. 35 cm,the minimum reflection loss reaches-13. 5 dB,and the bandwidth is 0. 7 GHz when the reflection loss is less than-10 dB. It means that M-type barium ferrite has good microwave absorption capability.