微波烧结制备镧钴取代的锶铁氧体永磁材料的性能研究
实验结果表明：随着烧结温度的增大，样品的剩磁Br和最大磁能积(BH)max先增大后减少，内禀矫顽力Hcj持续减小。铁氧体样品随着烧结温度的增大，烧结程度加强，晶粒逐渐长大，样品内部致密化。实验表明温度为1050℃时样品的磁性能最好，达到Br=416.5 mT,BHm=32.53 KJ/m3，这可能是微波烧结和离子取代共同作用的结果。SEM结果显示微波烧结出来的试样的晶粒尺寸相对传统的要小，并且晶粒尺寸分布更为均一。本实验所获得的初步结果对微波烧结和离子取代联合对锶铁氧体磁性能影响，进一步降低永磁铁氧体的成本有很好的指导意义。
关键词：锶铁氧体；离子取代；微观结构；磁性能；微波烧结
Study on microwave Sintering of Strontium Ferrite Permanent Magnetic Materials with La-Co ions partial replace
Abstract: Recently, in the field of permanent ferrite materials, ion-substitution is one of the effective methods that improve the magnetic properties of permanent ferrite materials. As for the La-Co-substitution and microwave sintering, the effect of different temperature and La-Co ions partial replace on the structure and magnetic properties of strontium ferrites is studied on paper.
The experimental results show that Br increased slowly at the beginning then decreased ,while Hcj decreased all the time with increasing temperature . With the sintering temperature increasing, grains gradually grow up and orientation becomes better. The experiment shows that the magnetic properties of samples by 1050℃ are the best, which reach Br=416.5 mT,BHm=32.53 KJ/m3 . The SEM results show that the sample grain size of microwave sintering is smaller than the traditional , and the grain size distribution is more uniform.The experiments show that La-Co ions partial replace and microwave sintering could improve the sample’s magnetic properties. This results have the guiding meaning in reducing the cost of permanent ferrite materials.
Key words: strontium ferrites; ion-substitution; microstructure; magnetic properties；microwave sintering
目录
1 绪论 1
1.1 磁性材料的简介 1
1.2 铁氧体材料的简介 1
1.3 永磁铁氧体的简述 2
1.4 永磁铁氧体材料的基本理论 2
1.4.1 永磁铁氧体的结构 2
1.4.2 永磁铁氧体的主要衡量指标 3
1.4.3 铁氧体材料制备方法 4
1.5 微波烧结法 5
1.5.1 微波烧结简介 5
1.5.2 微波烧结原理 5
1.5.3 微波烧结特点 5
1.6 离子取代方面的研究现状 6
1.6.1 La离子取代的研究 7
1.6.2 La-Co离子联合取代的研究 7
1.6.3 La-Zn离子联合取代的研究 8
1.7 本论文的研究目的和内容 8
2 实验原料、仪器和表征手段 9
2.1 实验原料与试剂 9
2.2 实验仪器与装置 9
2.3 样品制备方法 10
2.4 测试方法 10
2.4.1 磁性能 10
2.4.2 X射线衍射 11
2.4.3金相观察 11
3 实验方案确定和样品制备 13
3.1 实验配方的确定 13
3.2 实验制备过程 13
4实验结果和讨论 15