无重稀土烧结Nd-Fe-B磁体的显微结构和磁性能研究  

Study on Microstructure and Magnetic Properties of Heavy Rare Earth-Free Sintered Nd-Fe-B Magnets

作　　者：王亮 刘艳丽 马强 WANG Liang;LIU Yan-li;MA Qiang(School of Materials and Metallurgy,Inner Mongolia University of Science&Technology,Baotou 014010,China)

机构地区：[1]内蒙古科技大学材料与冶金学院,内蒙古包头014010

出　　处：《稀有金属与硬质合金》2023年第1期59-64,69,共7页Rare Metals and Cemented Carbides

基　　金：国家自然科学基金地区科学基金项目(51961031)。

摘　　要：对Ga、Al、Cu和Zr共同掺杂的烧结Nd-Fe-B磁体磁性能和显微结构进行研究,并通过回火工艺对磁体的矫顽力进行调控。结果表明:当一级回火为900℃×150 min,且二级回火为500℃×180 min时,磁体矫顽力H_(cj)从烧结态的14.33 kOe大幅提高到二级回火态的19.86 kOe,提高了38.6%;方形度H_(k)/H_(cj)由0.86增加到0.97;剩磁B_(r)仅从烧结态13.51 kGs略微下降到二级回火态的13.46 kGs;富稀土相分布更加连续和明显。研究分析表明,矫顽力大幅增加主要是由于含有少量的富Nd相和贫B相的烧结Nd-Fe-B磁体中Ga的掺杂改变了晶界相湿润性,降低了富稀土相中Fe元素的含量。本研究为无重稀土高矫顽力和高剩磁烧结Nd-Fe-B磁体步入产业化夯实了理论基础。The magnetic properties and microstructure of sintered Nd-Fe-B magnets co-doped with Ga,Al,Cu,and Zr were studied,and coercivity of the magnets was regulated by tempering process.The results show that when the first annealing is 900℃×150 min and the second annealing is 500℃×180 min,the magnet coercivity H_(cj)greatly increases from 14.33 kOe in the sintered state to 19.86 kOe in the second annealing state,which is a increase of 38.6%;rectangularity H_(k)/H_(cj)increases from 0.86 to 0.97;remanence B_(r)decreases slightly from 13.51 kGs in the sintered state to 13.46 kGs in the second annealing state;the distribution of RE-rich phase becomes more continuous and obvious.The research analysis shows that the reason why the coercivity greatly increases is that Ga doped in the sintered Nd-Fe-B magnets containing small amounts of Nd-rich phase and B-poor phase changes the wettability of intergranular phase and reduces Fe content in the RE-rich phase.The study lays a solid theoretical foundation for the industrialization of heavy rare earth-free sintered Nd-Fe-B magnets with high coercivity and high remanence.

关 键 词：无重稀土磁体 烧结ND-FE-B 磁性能 微观结构 矫顽力 

分 类 号：TM273[一般工业技术—材料科学与工程]