氧化物法低温烧结LiZn(Ti)铁氧体的球磨工艺、性能及显微结构

Milling Process, Properties and Microstructure of Low Temperature Sintered Li Ferrite Prepared by Oxide Method

以普通陶瓷工艺结合精细球磨制备了 Li0.365Zn0.27MnaFe2.365-aO4和 Li0.51Zn0.15Ti0.17MnaFe2.17-aO4铁氧体超细粉。研究了球磨时间和球质对粉料粒度的影响。实验表明,平均粒度随球磨时间的延长而减小,超过 15h球磨效率就十分低了,获得了<0.2μm的平均粒度。钢球和 ZrO2 球的球磨效果相近。给出了氧化物法、880±20℃下烧结的 Li0.365Zn0.27MnaFe2.365-aO4 的密度、收缩率和 Ms、?H 与烧结温度的关系,显示出良好的低温烧结特性。获得了在 880±10℃烧结温度下?H≤14kA/m,Ms=400(±5%)kA/m 的磁性能。SEM 照片表明氧化物法低温烧结样品的气孔率比 Sol-Gel 法样品的明显低。

The Li0.365Zn0.27MnaFe2.365-aO4 and Li0.51Zn0.15Ti0.17MnaFe2.17-aO4 fine ferrite powders were prepared by solid state reaction method, The particle size of the milling powders versus milling time was analyzed. The particle size decreases with prolonging milling time and after 1 5h the milling efficiency gets low, The milling efficiencies for using both iron ball and ZrO2 ball are similar. An average particle size of 0.2μm was obtained, The drawings of density and shrinkage, also saturation magnetization Ms and the ferromagnetic resonance linewidth A H versus sintering temperature at 88±20℃ for the Li0.365Zn0.27MnaFe2.365-aO4 ferrite are given, indicating a good low temperature sintering behavior. The properties of △H≤14kA/m,Ms=400（±5%）kA/m are obtained at sintering temperature 880±10℃. The SEM photographs show that the porosity of the sample prepared by oxide method is lower than that of the sample by sol-gel method.