氧化物法低温烧结Li系铁氧体的固相反应、致密化过程及微波性能  

Solid Reaction, Densification and Microwave Properties of Low Temperature Sintered Li Ferrites Prepared by Oxide Method

作　　者：韩志全[1] 廖杨[1] 冯涛[1] 

机构地区：[1]西南应用磁学研究所,四川绵阳621000

出　　处：《磁性材料及器件》2007年第2期23-25,39,共4页Journal of Magnetic Materials and Devices

摘　　要：采用普通陶瓷工艺结合精细球磨制备了Li0.5-0．5，ZnxMnaFe2.5-0.5x-aO4（0．1≤x≤0．6）和（LiFe）（1-x＋y）/2ZnxTiyFe2．5-x／2—3y／2MnaO4（0．1≤x≤0．25，0≤y≤0．4）铁氧体超细粉料（～200nm）。不同预烧温度粉料样品的XRD分析表明，生成尖晶石的固相反应从500～600℃开始，到700℃完成。预烧料的磁化强度．烧结温度曲线表明，大量生成磁性尖晶石相Li铁氧体的温度大约在550～700℃。在该LiZn铁氧体材料的烧结中出现了先膨胀后收缩的现象，致密化主要发生在固相反应基本完成之后。Li0.365Zn0.27MnaFe2.365-aO4的密度和收缩率、铁磁共振线宽△H和自旋波线宽△Hk、饱和磁化强度Ms和矫顽力Hc等性能参数的烧结温度曲线表明，在880±10℃下获得了良好低温烧结特性和电磁性能，特别是△Hk值为普通样品的3～4倍。根据饱和磁化强度的温度曲线，确定出Ms=400（1±5％），358（1±5％）和255（1±5％）kA／m材料的居里温度分别为475、540和430℃。The Li0.5-0.5XZnxMnaFe2.5-0.5x-ao4 （0.1≤x≤0.6） and （LiFe）（1-x＋y）/2ZnxTiyFe2.5-x/2-3y/2MnaO4（0.1 ≤ x ≤ 0.25, 0 ≤ y ≤ 0.4） ferrites were prepared by conventional ceramic technology combining fine milling. The XRD spectra show that the beginning of forming spinel phase is about 500-600℃ and the reaction ends at 700℃. The curve of reduced saturation magnetization for the samples pre-sintered at various temperatures shows that the temperature forming magnetic spinel is about 550-700℃. The shrinkage curve indicates that the expanding occurs first and then shrinking, and the densification occurs mainly at 800-850℃ after the solid reaction. The drawings of the density and shrinkage, also the ferromagnetic resonance linewidth AH and spin wave linewidth AHk, the saturation magnetization Ms and coercivity Hc, versus sintering temperature from 850 to 910℃ for the Li0.365Zn0.27MnaFe2.365-aO4 ferrite, were illustrated, which indicate that good low-temperature-sintering behavior, as well as microwave properties, were obtained at sintering temperature of 880±10℃. Especially, the values of AHk are 3-4 times higher than that of the common LiZn ferrite samples. From the temperature dependences of Ms for LiZn（Ti） ferrites with Ms=400, 358 and 255±5% kA/m, the Curie temperatures can be determined as 475, 540 and 430℃, respectively.

关 键 词：LIZN铁氧体 低温共烧 XRD分析 固相反应 铁磁共振线宽 自旋波线宽 

分 类 号：TM277[一般工业技术—材料科学与工程]