College of Materials Science and Engineering, Key Lab of Advanced Functional Materials, Chinese Education Ministry, Beijing University of Technology, Beijing, People's Republic of China.
Nanotechnology. 2010 Mar 19;21(11):115708. doi: 10.1088/0957-4484/21/11/115708. Epub 2010 Feb 22.
The single-phase ultrafine nanocrystalline SmCo(3) compound with a high coercivity of 33 kOe and a Curie temperature of 925 K was prepared using a simple and efficient method, which took advantages of the concurrent processes of nanocrystallization and densification during spark plasma sintering. The crystal structure of the nanocrystalline SmCo(3) compound was constructed. As compared with the conventional microcrystalline SmCo(3) compound, a large axial ratio c/a = 4.920 and an expansion of the unit cell volume of 2.97% were obtained in the lattice structure of the nanocrystalline SmCo(3). The relationship between the magnetic properties and the nanocrystalline structure was analyzed. A specific magnetic transition from the weak ferromagnetic to the strong ferromagnetic state was discovered in the nanocrystalline SmCo(3) compound, which was considered to be related to the large anisotropic strain in the crystal lattice.
采用一种简单高效的方法，通过火花等离子烧结过程中的同时纳米晶化和致密化过程，制备出单相超细纳米晶 SmCo(3)化合物，具有 33kOe 的高矫顽力和 925K 的居里温度。纳米晶 SmCo(3)化合物的晶体结构被构建。与传统的微晶 SmCo(3)化合物相比，纳米晶 SmCo(3)的晶格结构中获得了较大的轴比 c/a=4.920 和 2.97%的单位细胞体积膨胀。分析了磁性与纳米晶结构之间的关系。在纳米晶 SmCo(3)化合物中发现了从弱铁磁到强铁磁状态的特殊磁转变，这被认为与晶格中的大各向异性应变有关。
