Ba_2Ti_9O_(20)-BaFe_(12)O_(19)复合陶瓷电磁性能的研究

Dielectric and Magnetic Properties of Ba_2Ti_9O_(20)-BaFe_(12)O_(19) Composite Ceramics

本文采用流延成型法制备2-2型Ba2Ti9O20-BaFe12O19复合陶瓷。通过扫描电镜、能量散射光谱仪、X射线衍射、振动样品磁强计对复合陶瓷界面微观结构及磁、电性能进行了分析。结果表明:复合陶瓷的介电常数和介电损耗均大于单相Ba2Ti9O20,饱和磁化强度、剩余磁化强度均小于单相BaFe12O19,矫顽力大于单相BaFe12O19。随着烧结温度的升高,复合陶瓷的介电常数先增加后减小,介电损耗的变化则相反;饱和磁化强度、剩余磁化强度和矫顽力减小。在1180℃烧结4 h的复合陶瓷具有适合的磁、电性能:εr=115,tanδ=0.0054,Ms=21.9 A.m2/kg,Mr=12.5 A.m2/kg和Hc=63.0 kA/m。

In this paper,2-2 type Ba2Ti9O20-BaFe12O19 composite ceramics have been fabricated successfully by tape casting.The microstructure of interface and the dielectric and magnetic properties were characterized by scanning electron microscopy,energy dispersive spectroscopy,X ray diffraction as well as vibrating specimen magnetometer for the composite ceramics.The composites exhibit high dielectric constant and loss compared with pure Ba2Ti9O20,lower saturation magnetization and remnant magnetization than pure BaFe12O19 accompanied with a higher coercive field.The results show that the dielectric constant firstly increases and then decreases,while the dielectric loss has an opposite variation;the saturation magnetization,the remnant magnetization and the coercive field decrease with increasing sintering temperature.The composite sintered at 1180 ℃ for 4h has optimum dielectric and magnetic properties： εr=115,tanδ=0.0054,Ms=21.9 A·m2/kg,Mr=12.5 A·m2/kg and Hc=63.0 kA/m.