水热法合成无稀土永磁材料的研究
毕业论文关键词：水热合成法；纳米级钴；碳纳米管；热处理；ConC 粉体
Abstract Magnetic material plays an important role in the history of human civilization, which greatly promotes the communication and communication of world culture. Nowdays,the magnetic material is widely used in the field of information storage, motor, medical, magnetic separation etc. The paper is a study of ConC magnetic material system, which is not containing rare earth elements. Because Cobalt of hexagonal closed-packed has strong hard magnetic properties, and very large anisotropy. The whole process can be pided into three parts. Firstly, The experiment studies the technological conditions for nanometer cobalt by hydrothermal synthesis method. The results show that the optimum ratio of reaction raw materials, then controlling the heating time and temperature to compare the different properties of cob alt nanoparticles in different solvent thermal reaction. Secondly, after the nano cobalt and carbon nanotubes were vacuum packed, they were heat treated in the resistance furnace. This is mainly to study the synthesis and magnetic properties of ConC nanoparticles. Finally, in the experiment, the carbon nanotube is directly doped into the hydrothermal synthesis process of cobalt to study the amount of influence on the synthesis process and the resulting product structure. The results show that Sodium citrate and sodium hydroxide are two very important factors in the process of synthesis of cobalt. The concentration of sodium citrate affects the internal growth structure of cobalt synthesis. While sodium hydroxide acts as reducing agent, cobalt ions can be red uced to cobalt. ConC powders that were synthesized by heat treatment process of cobalt and carbon nanotubes. The ConC phase synthesized by this method is the mixed phase of Co, Co2C, Co3C and CoC8. And with the difference of heat treatment temperature, the magnetic properties of the sample are also different. Synthesis of ConC powders by direct addition of carbon nanotubes during hydrothermal synthesis process of cobalt. Compared with the sample without CNTs, the coercivity and saturation magnetization of the samples have been become larger.
Key Words：hydrothermal synthesis; nanometer cobalt; carbon nanotubes; heat treatment; ConC powder
目录
1绪论.1
1.1引言.1
1.2磁性材料.1
1.2.1硬磁材料1