摘要多铁性材料是指同时存在铁磁性、铁电性、铁旋性和铁弹性中的两种或两种以上性能的一类化合物。在一定温度下自发极化和自发磁化的同时存在可引起磁电耦合效应，使多铁性材料具有某些特殊的物理性质，并可引发一些新的、有意义的物理现象。磁电复合材料是多铁体材料中的一种，因其特有的磁电耦合机制，所以磁电复合材料有着非常广阔的应用前景。CoFe2O4/BaTiO3复合材料是一种典型的介电/铁磁复合材料，它同时具有可调控的容感两性。本设计以溶胶凝胶法为基础，通过改变BaTiO3在CoFe2O4溶胶凝胶工艺路线中的加入时间，即CoFe2O4凝胶阶段、CoFe2O4粉体合成后，制备了两种复合方式的CoFe2O4/BaTiO3复合材料。对制备合成后的CoFe2O4/BaTiO3复合粉体进行压片使其成为片状块体材料，并控制两相烧结温度、组份比例两个变量，制备合成不同系列的磁电复合材料样品。最后，对不同系列的样品进行XRD和铁电性能的测试，找到制备该复合材料的最优工艺参数和条件。47149

毕业论文关键词:CoFe2O4；BaTiO3；溶胶-凝胶法；多铁性材料

Abstract

Multiferroic material refers to a class of compounds exist ferromagnetism, ferroelectricity, iron and iron spin elasticity of two or more properties. At a certain temperature the spontaneous polarization and the simultaneous presence of spontaneous magnetization can cause magnetic coupling effect, the multiferroic material has some special physical properties, and raises some new, interesting physical phenomena. Magnetic composite material is a multiferroic material one, because of its unique magnetic coupling mechanism, the magnetic composite has a very broad application prospects. CoFe2O4/ BaTiO3 composite is a typical dielectric / ferromagnetic composites, it also has the capacity to control the sense of gender. This design is based sol-gel method, by changing the BaTiO3 in the sol-gel process route CoFe2O4 added time, that CoFe2O4 gel phase, after CoFe2O4 powder synthesis, CoFe2O4 / BaTiO3 Composites two complexes way prepared. For CoFe2O4 / BaTiO3 Composite Powder synthesized tabletting to become flaky bulk materials, and to control the two-phase sintering temperature and component ratio of the two variables, magnetic composite samples of different series of synthetic preparation. Finally, the samples were different series of XRD and ferroelectric properties of the test, the preparation of the composite material to find the optimal process parameters and conditions.

Keywords: CoFe2O4； BaTiO3； sol - gel method；Multiferroic material

目录

1 文献综述 3

1.1 磁电复合材料 3

1.2钛酸钡材料 4

1.3溶胶－凝胶法 5

1.4铁酸钴材料 6

1.5选题目的和意义 6

2 实验部分 7

2.1 实验内容 7

2.2 实验原料和实验仪器 8

2.3 仪器简介 9

2.3.1 热分析技术 9

2.3.2 XRD技术 10

2.3.3 铁电综合测试仪 11

2.4 实验过程 11

2.4.1 BaTiO3粉体制备 11

2.4.2 制备CoFe2O4粉体 12

2.4.3 CoFe2O4/BaTiO3复合粉体的制备 13

3 实验结果分析 14

3.1 BaTiO3合成工艺研究