摘要:作为一种重要的磁功能材料,正交钙钛矿结构 RFeO3(R 为稀土元素) 稀土铁氧体具有独特的磁性能,在稀土铁氧体中发现的激光诱导超快自旋重取向和多铁、磁电材料的发现,使稀土铁氧体成为凝聚态和材料物理中研究的热点。高质量的 RFeO3 晶体及相关材料的制备与相关特性研究,成为现代磁光和光磁研究的一个重要需求。 本文采用无容器气悬浮技术,制备了一系列不同组分的xSm2O3-(100-x)Fe2O3球体颗粒。在实验过程中,预处理的原料经过激光加热、快速冷却过程,从而实现快速结晶。此方法具有装置比较简单,操作起来非常方便;不需要通过反馈系统的方法来保持样品的平衡;控温方便,降温凝固速度较快;可以细化样品的围观组织,使样品的成分更加均匀,有利于新的亚稳相的形成;等优点。并利用XRD、SEM、VSM 等测试手段,详细分析了和研究了 xSm2O3-(100-x)Fe2O3的相关系、以及 SmFeO3 陶瓷颗粒的显微结构和磁性能。通过 XRDa 分析,发现Sm2O3/Fe2O3=50/50 下的物相单一,结晶度相比其他组份最好,其中Sm2O3/Fe2O3=30/50、60/40、70/30 下的结晶度也还可以,其他组分下的结晶度比较差。;通过扫描电镜分析 SmFeO3陶瓷的显微结构,SmFeO3陶瓷的表面以树枝晶的形式进行生长,同时呈现出一定的取向,深色的树枝晶间规则排列着明亮的析出物;通过对SmFeO3进行磁性分析,发现铁和稀土原子的磁矩以及它们之间的作用形成了ReFeO3有趣的磁性行为。由于正交相的对称性较低,FeO6正八面体发生倾斜,这产生了弱铁磁性。 41190
毕业论文关键词:钙钛矿型化合物;RFeO3;磁性能;气悬浮技术
Study on Preparation of RFeO3 air suspension system and related physical characteristics
Abstract:As a kind of important functional materials, orthorhombic perovskite structure RFeO3 (R is rare earth element) of rare earth ferrite with unique magnetic energy, found in the rare earth ferrite laser induced ultrafast spin reorientation and iron, magnetic materials, rare earth ferrite becomes condensed state and materials physics in the study of hot. RFeO3 crystals with high quality and related materials, preparation and characteristics of, become a significant requirement for modern magnetic optical and magneto-optical studies. In this paper, a series of xSm2O3- (100-x) Fe2O3 spherical particles with different components were prepared by the technology of non vessel gas suspension. In the process of experiment, the raw material is heated and cooled fast, so as to realize rapid crystallization. This method is relatively simple, the operation is very convenient; do not need the feedback system to keep the sample balance; temperature control and convenient, cooling solidification speed faster, refinement of the samples of the onlookers organization, the sample composition is more uniform, is conducive to the new metastable phase formation; advantages. And the XRD, SEM, VSM and other testing methods were used to analyze and study the correlation of xSm2O3- (100-x) Fe2O3 and the microstructure and magnetic properties of SmFeO3 ceramic particles. By XRD analysis, it is found that the single phase of the Sm2O3/Fe2O3=50/50, crystallinity compared to other components the best, which Sm2O3/Fe2O3=30/50, 60 / 40 and 70 / 30 crystallinity can also, other components of the crystallization degree is poor. ; SmFeO3 ceramic microstructure was analyzed by scanning electron microscopy (SEM) and SmFeO3 ceramic surface in form of dendritic growth, while showing a certain orientation, dark interdendritic rule lined with bright precipitates; through the magnetic analysis of SmFeO3, found iron and dilute and their magnetic moments of Tsuchihara Ko formed RFeO3 interesting magnetic behavior. Due to the lower symmetry of the quadrature phase, the FeO6 is tilted to the eight plane, which produces a weak ferromagnetic property. 气悬浮技术制备RFeO3体系及其相关物理特性研究:http://www.youerw.com/cailiao/lunwen_41171.html