高性能各向异性Sm_2Co_(17)纳米永磁材料的制备与表征

Preparation and characterization of high-performance anisotropic nanostructured Sm_2Co_(17) permanent magnetic materials

利用表面活性剂辅助高能球磨(SA-HEBM)分别制备了高性能的各向异性Sm2Co17纳米永磁粉末材料,然后对球磨产物进行超声波分散清洗。利用高速离心技术进行纳米颗粒分级,获得颗粒尺寸分布狭窄的纳米永磁颗粒,对所得粉末进行适当的快速热处理。分别采用扫描电镜、X射线衍射和振动样品磁强计分析、测试样品的显微形貌、相结构和室温磁性能。结果表明,粉末的厚度在80 nm左右,长度为亚微米级,具有高比表面积、强形状各向异性与磁各向异性;经过磁场取向后,Sm2Co17的易磁化轴和难磁化轴方向的室温矫顽力分别达到612.9 k A/m(7.7 k Oe)和278.6 k A/m(3.5 k Oe);表面活性剂在球磨过程中起到了重要作用。

In this study, Sm-Co nanoflakes were prepared by surfactant assistant high-energy ball milling （SA-HEBM） using oleylamine and oleic acid as the surfactant. The microstructure, crystal structure and magnetic properties were examined with scanning electronic microscopy （SEM）, X-ray diffraction（XRD）, and vibrating sample magnetometer （VSM）, respectively. Results show that the powder with about 80 nm thickness and sub micron length are of high specific surface area, strong shape anisotropy and magnetocrystalline anisotropy; after field - orientation, the room temperature coercivity values in the easy-axis and hard-axis direction of Sm2Co17 powders were 612.9 kA/m （7.7 kOe） and 278.6 kA/m （3.5 kOe）, respectively;surfactant plays an important role in the milling process.