纯稀土纳米晶Gd块体材料的结构与磁性  

Structure and magnetic properties of of bulk nanocrystalline gd metal

作　　者：岳明[1] 王克军[1] 曾宏[1] 刘程扬[1] 张久兴[1] 

机构地区：[1]北京工业大学新型功能材料教育部重点实验室,北京100022

出　　处：《功能材料》2007年第A10期3959-3961,共3页Journal of Functional Materials

基　　金：国家自然科学基金资助项目（50201001）;北京市自然科学基金资助项目（2041001）

摘　　要：采用放电等离子烧结技术（简称SPS技术）及热处理制备了全致密纯稀土纳米晶Gd块体材料，研究了材料的微结构和磁性。X衍射结果表明材料在烧结过程中形成了一定程度的c轴织构。TEM观察显示，烧结态纳米晶Gd的平均晶粒尺度在10nm左右；热处理后，平均晶粒尺寸达到100nm。PPMS测试发现与粗晶Gd相比，纳米晶Gd的居里温度以及饱和磁化强度均有所下降。说明Gd的纳米化对其磁性具有重要影响。Spark Plasma Sintering （SPS） and subsequent annealing technique was applied to prepare full dense bulk nanocrystalline Gd metal. XRD results show that there is a pressure-induced C-axis crystal texture in the SPS and annealing Gd samples. TEM observation shows that SPS Gd metal has a single phase with a mean grain size of about 10 nm. After heat treatment, the grain size increases to 100 nm. With decrease of Gd grains from micrometer- to nanometer- size, the Curie temperature Tc is decreased by 11.7 K and the magnetic moment per Gd atom at 5 K drops evidently from 7.81 μB to 6.31 μB. These results indicate a remarkable influence of the nanostructure on the magnetism of Gd due to finite size effect.

关 键 词：GD 纳米晶块体 SPS 

分 类 号：TM271[一般工业技术—材料科学与工程]