添加CaF2对烧结稀土永磁体性能的影响

用添加CaF2的方法制备了烧结Nd-Fe-B和烧结Sm-Co复合磁体，并对磁体的性能进行了分析研究。实验结果表明，在添加CaF2的烧结Nd-Fe-B复合磁体的电阻率增大，但其磁性能有一定程度的下降；而添加CaF2的烧结Sm-Co复合磁体，由于制备工艺过程中的氧化问题，导致磁体的磁性能严重下降。扫描电镜分析表明，烧结Sm-Co/CaF2复合磁体中没有形成1：5相和2：17R相的微观组织；在烧结Nd-Fe-B/CaF2复合磁体中，CaF2只存在于晶界富Nd相中，对磁体的微观组织没有太大的影响，烧结Nd-Fe-B磁体适合用添加CaF2的方法制备高电阻率的复合磁体。

Effect of adding on the performance of sintered rare earth permanent magnets

Sintered Nd-Fe-B and Sm-Co composite magnets were prepared by adding calcium fluoride and their properties were investigated. Experimental results show that the electrical resistance of the sintered Nd-Fe-B magnets with CaF2 increased, but their magnetic properties decrease to some extent. The magnetic properties of the sintered Sm-Co magnet with CaF2 decreased seriously due to the oxidation during the preparation process. The scanning electron microscopy results show that there did not form 1:5 phase and 2:17R phase in microstructure of the sintered Sm-Co/CaF2 composite magnet. The CaF2 was distributed in the grain boundary attached to the Nd-rich phase and has a little effect on the microstructure of sintered Nd-Fe-B/CaF2 composite magnet. It is a way to increase the electrical resistance for the sintered Nd-Fe-B magnet by adding CaF2.