文档介绍：河北工业大学
毕业论文
作者: 张凤祥学号: 101954
学院: 材料科学与工程学院
系(专业): 材料物理(功能材料方向)
题目: Sm-******@Fe-Co核壳结构复合纳米颗粒的制备
及磁性能
指导者: 步绍静副教授
(姓名) (专业技术职务)
评阅者:
(姓名) (专业技术职务)
2014年5月29日
毕业设计(论文)中文摘要
题目:Sm-******@Fe-Co核壳结构复合纳米颗粒的制备及磁性能
摘要:
硬/软复合磁性材料可以结合硬磁性相高的矫顽力和软磁性相高的饱和磁化强度的优点,并通过两相之间的交换耦合作用获得更高的最大磁能积等综合磁性能。,通过溶剂热合成法在其上包覆Fe-Co软磁壳层,制备具有“核壳”结构的Sm-******@Fe-Co纳米颗粒,考察工艺参数对颗粒微观结构及磁性能的影响。研究发现,溶剂热反应时间、金属离子价态、前驱体溶液中金属离子浓度比等对软磁壳层的成分、相结构及颗粒尺寸等有重要影响。以Fe3+和Co2+为原料在Sm-Co颗粒表面同时沉积Fe、Co可以得到Fe-Co化合物软磁壳层。由于核壳之间界面结合较弱,使得核/壳之间的交换耦合效应受到抑制,在一定程度上阻碍了复合颗粒磁性能的提高。。
关键词:核壳结构纳米颗粒水热法交换耦合核壳结构磁性能溶剂热法
毕业设计(论文)外文摘要
Title Research on the Preparation and ic Properties of
Sm-******@Fe-Co ic Nanoparticles with a Core-Shell
Microstructure
Abstract
In order to obtain the ic materials with more excellent integrated ic performance, the method of exchange coupling between hard and soft ic phases has been used to integrate the characteristics of these two phases, resulting in both the high saturation ization and high coercivity. In this thesis, Sm-******@Fe-Co ic nanoparticles with a core-shell microstructure were prepared by the hydrothermal synthesis method. The microstructure and ic properties of Sm-******@Fe-Co ic nanoparticles with a core-shell microstructure were analysed by TEM, XRD and VSM. The influences of technological parameters, such as ratio of raw materials and the heat preservation time, etc, on the microstructure and ic properties of nanoparticles were studied. The results show that the Co2+ were reduced to relatively pure Co particles by hydrazine hydrate. As the extension of time Co particles grew up obviously and the properties of coating were deteriorate along with the growing of particles. The Fe2+ all turned to Fe3O4 after the reaction, the Fe3+ can produce a little pure Fe particles, but the quantity is too little to have a significant influence on the ic properties. The Fe3O4 can also cover the Sm-Co ic nanoparticles to improve their ic properties to some extent. There