Nd-Fe-B非晶合金晶化过程中亚稳相形成的控制与磁性增强研究

采用熔体快淬技术制备Nd-Fe-B贫Nd非晶合金。通过改变合金熔体温度和采用严重塑性变形技术来调控Nd-Fe-B非晶合金退火晶化过程中亚稳相的形成与演变、软/硬磁纳米晶的形成和微结构。探索熔体温度对快淬非晶合金晶化制备的a-Fe/Nd2Fe14B纳米晶复合永磁材料的界面结构与化学的影响。研究合金熔体温度－亚稳相形成与演变和纳米晶微结构－磁性能之间的关系。研究室温塑性变形对非晶合金晶化制备的纳米晶复合永磁材料的界面结构与化学的调控。研究塑性变形加工参数－亚稳相形成与演变和纳米晶微结构－磁性能之间的关系。将熔体温度的控制与室温塑性变形技术相结合，来调控非晶合金晶化过程中亚稳相的形成和演变行为，开展a-Fe/Nd2Fe14B纳米晶的界面结构与化学的调控研究。研究纳米晶的界面结构和化学对合金矫顽力机制、畴壁钉扎强度和磁性增强的影响。开展高性能a-Fe/Nd2Fe14B块体纳米晶复合永磁材料的研究。

In this project, Nd-lean amorphous Nd-Fe-B alloys are prepared by melt-spinning technique. By varying the temperature of alloy melt and employing severe plastic deformation (SPD), the formation and evolution of metastable phases and the microstructures of soft/hard-magnetic nanocrystals formed in thermal crystallization processes of amorphous Nd-Fe-B will be stdudied. The effect of the temperature of melt on the interfacial structure and chemistry of ?a-Fe/Nd2Fe14B nanocomposite magnets produced by annealing amorphous Nd-Fe-B will be investigated. We will study the relationships between the melt temperature - metastable phase formation and evolution as well as nanocrystalline microstructure - magnetic properties. The interfaces of ?a-Fe/Nd2Fe14B nanocomposite magnets yielded from the thermal crystallization of amorphous Nd-Fe-B will be tuned via SPD technique. Moreover, the processing-microstructure-property relationships will be studied. Furthermore, the interfaces of ?a-Fe/Nd2Fe14B nanocomposite magnets will be effectively tuned by a combination of varying the temperature of melt and SPD technique via controlling metastable phase formation. The effect of nanocrystalline interfaces on coercivity mechanism, domain-wall pining and magnetic properties will be studied in details. Finally, the preparation of high-performance ?a-Fe/Nd2Fe14B bulk nanocomposite magnets will be performed in the present project.