极端热变形条件下非晶合金的纳米晶化研究对先进纳米晶材料的发展具有重要意义。本项目瞄准纳米复合永磁材料研究中软磁纳米晶的形态(尺寸、含量和分布)控制与永磁纳米晶织构形成相矛盾这个关键科学问题，拟采用强力轧制技术产生高应力(>600 MPa)、大应变(>80%)，研究这种极端热变形条件下含软磁纳米晶的Nd-Fe-B非晶合金的晶化动力学、永磁纳米晶的取向生长和纳米晶结构演变。研究变形工艺参数对永磁纳米晶织构形成和软磁纳米晶形态的调控作用；研究预存软磁纳米晶的形态演变及其对永磁纳米晶取向生长的影响；弄清高应力、大应变条件下永磁纳米晶织构的形成机制；建立“变形工艺参数－微结构－磁性能”之间的关系，在此基础上制备高性能、大尺寸各向异性纳米复合永磁材料。本项研究将对我们探索极端条件下先进纳米晶材料的制备提供基础，推动高性能纳米永磁材料的发展。

Studies on the nanocrystallization of amorphous alloys under extreme conditions are of great significance to developing nanocrystalline materials. This project aims at a key scientific problem faced by nanocomposite magnets that controlling the size, fraction, distribution of the soft magnetic nanocrystals are contradictory to the oriented growth of the hard ones. We will study the crystallization kinetics, oriented growth and microstructure evolution of the NdFeB nanocrystals from the amorphous alloys under extreme-conditioned thermal deformation with a high stress (>600 MPa) and a large strain (>80%). The effects of the deformation parameters on the oriented growth of the NdFeB nanocrystals and the microstructure of the soft magnetic nanocrystals will be studied and the texture formation mechanism of the NdFeB nanocrystals will be clarified. The microstructure evolution of the soft magnetic nanocrystals and its effect on the oriented growth of the NdFeB nanocrystals will be investigated. The relations between deformation parameters, microstructure and magnetic properties of the prepared magnets will be established. On the basis, a high-performance anisotropic bulk nanocomposite magnet with a large size is expected to be prepared. These studies will provide an effective strategy to fabricate nanomaterials and will promote the development of the strong nanostructured permanent magnets.