块体SmCo7/Nd2Fe14B异质纳米复合永磁体的微结构和磁性能

Microstructure and Magnetic Properties of the Bulk Anisotropic Nanohybrid SmCo7/Nd2Fe14B Magnets

采用高压热压缩变形技术对高能球磨的SmCo基非晶-纳米晶粉体与商用的Nd-Fe-B纳米晶粉体的混合物冷压块进行变形处理,成功制备出块体各向异性SmCo7/Nd2Fe14B异质纳米复合永磁体。通过X射线衍射仪(XRD)、透射电子显微镜(TEM)以及振动样品磁强计(VSM)对块体SmCo7/Nd2Fe14B异质纳米复合永磁体的微结构和磁性能进行分析研究得出:所制备磁体的微结构由SmCo7/Nd2Fe14B纳米晶区域组成,且SmCo7/Nd2Fe14B纳米晶具有沿其(00l)方向(平行于压力方向)的择优取向;磁体具有明显的磁各向异性,室温下沿压力方向具有16MGOe的最大磁能积;磁体具有较好的温度稳定性,其矫顽力温度系数β(RT-250℃)=-0.26%℃^-1。研究结果表明,所制备磁体具有较高的潜力,可应用于国防军工、轨道交通等科技领域。

By using high-pressure thermal compression(HPTC),the blends of SmCo-based amorphous-nanocrystalline powders and the commercial Nd-Fe-B nanocrystalline powders were deformed,and the bulk anisotropic nanohybrid SmCo7/Nd2Fe14B magnets were successfully prepared.The microstructure and magnetic properties of the obtained magnets were studied by XRD,TEM and VSM.The experimental results show that the obtained SmCo7/Nd2Fe14B magnets are composed of SmCo7 and Nd2Fe14B nanocrystalline regions,and the SmCo7 and Nd2Fe14B nanocrystals possess a(00 l)texture along the pressure direction(parallel to the pressure direction).Magnets exhibit an obvious magnetic anisotropy and a maximum energy product of 16 MGOe at room temperature(RT)along the pressure direction.Moreover,the obtained magnets have a good thermal stability with a lowβ(RT-250℃)=-0.26%℃^-1.These findings demonstrate that the bulk anisotropic nanohybrid SmCo7/Nd2Fe14B magnets have high potential to be applied in national defense,military industry,rail transit and other scientific and technological fields.