摘要
在氮气中合成了单相的亚微米级MnZn铁氧体粉体,利用XRD、TG-DTA及热膨胀仪表征了空气环境下铁氧体的物相、质量和尺寸随温度改变的变化规律,研究了加热过程中铁氧体的氧化特性及其对烧结的影响。结果表明,铁氧体的Mn、Fe离子在升温过程中易发生氧化还原反应,从而在500℃时析出Fe2O3,离子变价使得尖晶石结构中的部分金属离子在四面体位和八面体位之间发生迁移,导致立方结构晶格畸变,使铁氧体产生质量变化和形变,进而引起烧结过程中出现裂纹。
Pure-phase submicro-sized MnZn ferrite powder prepared by solid-state reaction in nitrogen was annealed in air to explore its oxidation characteristics that occur in the heating-up stage for sintering and their impact on sintering. The effects of heating temperature on the changes in crystalline lattice parameter, phase composition, sample mass and material shrinkage were investigated by XRD, TG-DTA and dilatometry. It is found that due to the easy change of chemical valences of Mn-ions and Fe-ions, MnZn ferrite may undergo a series of redox reactions during the heating process. MnZn ferrite partially decomposes to FeaO3 impurity at 500 ℃. The metal ions are migrated between tetrahedral and octahedral sites in the spinel structure, which results in crystal lattice distortion, mass variation, sample deformation and thereby cracking in sintering process.
出处
《电子元件与材料》
CAS
CSCD
北大核心
2014年第1期15-20,共6页
Electronic Components And Materials
基金
长江学者和创新团队发展计划资助项目(No.IRT1146)
江苏省研究生科研创新计划资助项目(No.CXZZ12_0407)
关键词
MNZN铁氧体
氧化特性
离子变价
相变
形变
裂纹
MnZn ferrite
oxidation characteristics
change of ions＇ valences
phase change
deformation
cracking
