MnO_2对镍铁尖晶石烧结行为及磁性的影响  

Effect of MnO_2 Addition on Sintering Behavior and Magnetic Property of Nickel Ferrite Spinel

作　　者：杜金晶[1] 刘宜汉[1] 姚广春[1] 张啸[1] 

机构地区：[1]东北大学材料与冶金学院,辽宁沈阳110819

出　　处：《东北大学学报（自然科学版）》2011年第10期1452-1455,共4页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金重点资助项目(50834001);国家高技术研究发展计划项目(2009AA03Z502)

摘　　要：通过两步固相反应法合成了不同MnO2质量分数的NiFe2O4尖晶石.利用扫描电镜、X射线衍射仪、差热分析仪、热膨胀仪和振动样品磁力计,分别对样品的结构、物相变化、烧结行为和磁性进行了研究.结果表明,添加的MnO2在烧结过程中发生了分解反应,Mn元素以Mn2+,Mn3+形式进入NiFe2O4尖晶石晶格中,样品无新相生成,材料仍是镍铁尖晶石结构.另外,MnO2能够促进烧结,添加1%MnO2后试样收缩速率达到最大时的温度比纯镍铁尖晶石低59°C.添加1%MnO2时,试样的饱和磁化强度(Ms)和矫顽力(Hc)分别为15.673 emu/g和48.316Oe.NiFe2O4 spinel samples with different mass fractions of MnO2 were synthesized by two-step solid phase sintering process.The morphology and phase transformation were examined by scanning electron microscopy,X-ray diffraction and DTA analysis,respectively.The sintering behavior and magnetic property were investigated by thermal expansion instrument and vibrating sample magnetometer,respectively.The results showed that MnO2 decomposes into MnO and Mn2O3,the crystalline structure of the ceramic matrix is still of NiFe2O4 spinel and no other new phases appear.MnO2 addition can promote sintering obviously,the temperature where maximum shrinkage rate is attained for 1% MnO2-doped samples is 59 ℃,lower than that for un-doped samples.The saturation magnetization and coercivity are 15.673 emu/g and 48.316 Oe,respectively for 1% MnO2-doped samples.

关 键 词：镍铁尖晶石 添加剂 二氧化锰 烧结行为 磁性 

分 类 号：TF125.4[冶金工程—粉末冶金]