热处理对烧结NdFeB磁体微观结构和磁性能的影响

Effect of Annealing on Microstructure and Magnetic Properties of Sintered NdFeB Magnets

摘要:

系统研究了热处理对烧结NdFeB磁体微观结构和磁性能的影响.结果表明：二级回火热处理后,磁体微观组织结构得到明显改善,晶界变得更加规整、平滑,富Nd相均匀弥散地分布于晶粒周围,晶界相成分趋于稳定、均匀;磁体的内禀矫顽力显著提高,剩磁及最大磁能积也有一定程度的提高,极大地改善了磁体的热稳定性.

关键词:热处理 微观结构 磁性能 烧结NdFeB磁体 热稳定性

Abstract:

The effect of annealing process on the microstructure and magnetic properties of sintered NdFeB magnets were studied. The results show that the microstructure of magnets is ameliorated after annealing. The grain boundary became smoother and clearer, the Nd-rich phase distributed surrounding the grain dispersedly and equably, and the boundary phase became stable and well-proportioned. Therefore, the coercive force was remarkably enhanced, the residual magnetism and (BH) max were increased at the same time, and thermal stability of the magnet was improved enormously.

Key words:annealing; microstructure; magnetic properties; sintered NdFeB magnets; thermal stability