BaM、BaCoTiM、BaZnTiM的柠檬酸溶胶-凝胶合成及其微波介电性能、磁性能研究

Studies on preparation, dielectric and magnetic properties of BaM,BaCoTiM,BaZnTiM ferrites by citrate sol-gel process

采用柠檬酸sol gel工艺,以柠檬酸铁、碳酸钡、硝酸钴、硝酸锌、钛酸四丁酯以及柠檬酸等为原料合成了BaFe12O19、Ba(CoTi)xFe12-2xO19、Ba(ZnTi)xFe12-2xO19(x=0.2、0.6、1.0)铁氧体。采用XRD、SEM对其相成分和显微结构进行研究。并对其复介电常数、复磁导率在1MHz～6GHz下的变化规律进行了研究。结果表明3种铁氧体的复介电常数随微波测试频率的增加而变小,其磁导率虚部随测试频率的变化曲线上显示出非常明显的由畴壁共振引起的共振峰,该共振峰随铁氧体粉末热处理温度的升高移向低频。

BaFe12O19, Ba(CoTi)xFe12-2xO19, Ba(ZnTi)xFe12-2xO19 (x=0.2, 0.6, 1.0) ferrites were prepared by citrate sol-gel process using Fe(NO3)3, BaCO3, Co(NO3)2, Zn(NO3)2, Ti(OC4H9)4 and citrate acid as raw materials; Several methods such as X-ray diffraction and scanning electron microscopy were used to obtain detailed information on the crystallography of the precursor powders calcined at different temperature. The complex dielectric constant and complex permeability dispersion were investigated in 1 MHz-6 GHz ranges. It was discovered that the complex dielectric constants of all ferrites decrease with the increase of measuring frequency. Very obvious resonance phenomena due to domain wall resonance were observed for all samples in which corresponding frequency shifts to lower frequency as annealing temperature increases.