Nd9.5Fe81Zr3B6.5纳米复相永磁材料的物相演变及磁性能

摘要

Melt-spun Nd9.5Fe81Zr3B6.5 ribbons were prepared by the melt-spinning technique. The phase evolution and magnetic properties were studied by X-ray diffraction, differential scanning calorimetry, transmission electron microscopy observations, and magnetization measurements. It is indicated that melt spinning at different wheel velocities caused the as-quenched ribbons to have distinctive structure. The phase transformation of the ribbons during annealing takes place in two steps: α-Fe transforms from the amorphous phase firstly, followed by formation of Nd2Fe14B phase. With increasing the initial quenching rate, the microstructure of optimally heat treated ribbons becomes coarser, which results in the weakening of the exchange coupling effect between the hard and soft phase. This leads to drastic deterioration of magnetic properties of annealed ribbons with increasing the initial quenching rate.%利用单辊快淬法制备Nd9.5Fe81Zr3B6.5合金条带，采用X射线衍射、差式扫描热分析、透射电子显微分析和振动磁强计等分析测试手段，对合金条带的物相演变和磁性能进行研究。结果表明：在不同快淬速度的条件下，合金条带的微观组织结构不同；在热处理过程中，合金的晶化过程分两步完成：α-Fe 首先析出，Nd2Fe14B 随后析出。随着快淬速度的增大，最佳热处理后合金的晶粒变粗，这使得软磁相和硬磁相之间的交换耦合作用减弱，进而导致合金磁性能的降低。