声化学法与放电等离子烧结制备Nd-Fe-B/α-Fe纳米晶复合磁体

Nd-Fe-B/α-Fe nanocomposite mangets prepared by sonochemistry and spark plasma sintering

采用声化学法制备Nd-Fe-B/α-Fe型双相包覆磁粉，再经放电等离子烧结（SPS）制备成致密块状磁体．研究了不同α-Fe包覆含量对复合磁体磁性能及微观结构的影响．结果表明，声化学法可以制备均匀混和的双相纳米磁粉，α-Fe纳米粉均匀的包覆在硬磁相颗粒周围．烧结后的各向同性磁体有明显的剩磁增强，具有较高的磁性能．当α-Fe包覆量为2％（体积分数）时，磁体性能最佳，其（BH）max值为148．64kJ/m^3．

Nd-Fe-B/α-Fe two-phase magnetic powders were obtained by sonochemistry method. Bulk Nd-Fe-B/α-Fe nanocomposite magnets were created successfully by hot pressing the powders using SPS. Effect of α-Fe content on magnetic properties and microstructure of the nanocomposite magnets was studied. Nano-sized α-Fe coating NdFeB two-phase powders were obtained by sonochemistry method; the two phases mixed homogeneously. The Nd-Fe-B/α-Fe magnets showed remanence enhancement and high magnetic properties after SPS hot press. Under optimum α-Fe content （2 vol %）, bulk NdFeB/α-Fe possessed （BH）max= 148.64kJ/m^3.