焙烧对溶胶-凝胶自蔓延燃烧法制备的钡铁氧体粉体相成分与磁性能的影响

Influence of Roasting on the Phase Composition and Magnetic Properties of BaFe_(12)O_(19) Nanoparticles Prepared by Sol-Gel Self-propagation High-temperature Synthesis

为了制备综合性能优良的钡铁氧体,利用溶胶-凝胶自蔓延燃烧法,通过改变凝胶燃烧时间和焙烧条件制备了均相钡铁氧体粉末。用 X 射线衍射(XRD)仪、振动样品磁强计(VSM)、透射电镜(TEM)对热处理后的样品进行分析。结果表明,当柠檬酸/阳离子摩尔比为2.75、460℃燃烧 1h、520℃预烧5h、880℃焙烧5h 时,可制得单一均相 BaFe12O19,该产物具有较高的矫顽力(459 kA/m)、饱和磁化强度(58.4A·m2/kg)和剩余磁化强度(34.8A·m2/kg)。TEM 照片显示晶粒度在 30～80nm。通过本实验研究制得了磁性能优良、晶型完整的纳米钡铁氧体粉末。

Barium ferrite nanoparticles were prepared by sol-gel method combining SHS technique by varying inflaming time and heat treated process. Heat treated specimens were characterized using X-ray diffraction, vibrating sample magnetometer （VSM） and transmission electron microscopy （TEM）. Thc results show that single uniform BaFe12O19nanoparticles were prepared beselecting the citric acid to cation mole ratio of R=2.75, inflaming the gel at 460℃ for lh, preheating at 520℃ for 5 hand heat treating at 880℃ for 5 h, which features high coercivity （459kA/m）, saturation magnetization （58.4A ·m^2/kg） and remanent magnetization（34.8 A·m^2/kg）. TEM analysis indicated that the particle sizes of the barium ferrite are between 30 to 80 nm.