高矫顽力烧结钕铁硼永磁研究进展

Research Progress of Sintered Nd-Fe-B Permanent Magnets With High Coercivity

烧结钕铁硼稀土永磁具有超高的磁性能,但是居里温度较低,使其在高温领域的应用受到一定的限制.新能源汽车、风力发电等新兴产业的快速发展,大幅拉升了对耐高温烧结钕铁硼的市场需求.因此,为了提高钕铁硼材料的使用温度,通过开发新技术来提高烧结钕铁硼矫顽力;同时,为了降低产品成本和对重稀土金属的消耗,开发低Dy或无Dy的高矫顽力烧结钕铁硼磁体成为目前的研究热点.研究发现,采用细化晶粒技术、晶界扩散技术以及晶界掺杂技术均能不同程度地提高钕铁硼磁体的矫顽力.综述了这3种新技术的最新研究进展.

Sintered Nd-Fe-B rare earth permanent magnets have excellent magnetic properties. But its Curie temperature is low,which makes it limited in the field of high temperature applications. With the rapid development of new energy vehicles,wind power and other emerging industries,the market demand for high temperature sintered Nd-Fe-B magnets have been greatly raised. Therefore,in order to improve the service temperature of Nd-Fe-B material,new technologies have been developed to increase the coercivity of sintered Nd-Fe-B magnets. At the same time,the investigation on the high coercivity sintered Nd-Fe-B magnets with low Dy content or without Dy content become the highlights in order toreduce the product cost and consumption of heavy rare earth metals. It is found that the coercivity of Nd-Fe-B magnets can be improved to a certain extent by refined grain technology,grain boundary diffusion technology and grain boundary doping technology. In this paper,the latest research progress of these three new technologies are reviewed.