Synthesis and Characterization of Radar Absorbing Materials of Ba1-XLaXFe12O19+0.5X/BaTiO3

• Main Authors: HSU,CHIA-WEI, 徐嘉偉
• Other Authors: CHENG,KEN-FA
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/49ed93

碩士 === 國防大學理工學院 === 化學工程碩士班 === 105 === In this study, the high temperature was used to provide enough energy for fabricating the M-type microwave-absorbing materials Ba1-xLaxFe12O19-0.5x with the solid state reaction method. XRD patterns revel that the M-type Hexagonal crystal occurs along with α-Fe2O3 phases at 900℃ with 4 hours of a heating condition. When the temperature increased to 1300℃ in 4 hours, the alpha-Fe2O3 phases disappeared. It is also observed that the M-type Hexagonal crystal particle size increases with increasing temperature by using FE-SEM. The particle sized reaches up to 25um~50um at 1300℃in 4 hours. The magnetic hysteresis loop results indicated that the Ms, Mr, and Hc values of the M-type Hexagonal ferrite crystals are dependent on the calcing temperature and the chemical composition of materials. In which Ms and Mr decrease with increasing x value, while the Hc increases with increasing x value. The value of saturated magnetization (Ms) increases with increasing temperature and the value of Hc decreases with increasing temperature. The composite microwave-absorbing materials made by mixing the thermoset rubber (RTV-165) with hexagonal ferrites (7:3 by weight) were found having an obvious microwave-absorbing effect. A 1mm-thick of the composite material (Ba0.6La0.4Fe12O19.2/RTV-615) has about -4dB and -9dB of deflection loss at 9~11GHz and 16~18 GHz of electromagnetic radiation, respectively. The composite material of Ba0.6La0.4Fe12O19.2/ SiC /RTV-615 has the reflection lose -12dB at 17~18GHz.