镝氢化物掺杂钕铁硼稀土永磁体的研究  

Nd-Fe-B Sintered Magnets with Dysprosium Hydride Addition

作　　者：向丽君[1] P.J.McGuiness Robin Stuart Mottram 闫阿儒[4] 胡伯平[5] 严高林[1] 

机构地区：[1]武汉大学物理科学与技术学院,湖北武汉430072 [2]斯迪文研究院 [3]伯明翰大学冶金与材料学院 [4]中国科学院宁波材料与工程研究所,浙江宁波315201 [5]中国科学院北京三环新材料高技术公司,北京100080

出　　处：《中国稀土学报》2014年第5期555-562,共8页Journal of the Chinese Society of Rare Earths

基　　金：国家科技部国际科技合作与973预研项目(2014DFB50130;2011CB612304);国家自然科学基金项目(51172168;51072139)资助

摘　　要：发现了采用减量化重稀土镝添加高效制备块状超高矫顽力稀土永磁体新型方法。在钕铁硼（Nd-Fe-B）系稀土永磁材料中以DyH3的形式掺入稀土镝（Dy）元素,在不同烧结温度1020,1040,1050,1060,1080℃下进行烧结,制备成一系列DyH3掺杂（PrNd）30Fe69B磁体和未掺杂的（PrNd）30Fe69B磁体。研究剩磁、矫顽力与烧结温度及显微结构之间的关系。结果显示：随着温度的升高,剩磁不断上升;矫顽力在烧结温度1020-1050℃时达到最大。重稀土Dy添加可有效增加Nd-Fe-B磁体的矫顽力。采用扫描电镜和能谱仪研究了不同烧结温度对磁体晶粒尺寸、Dy在晶粒内与晶界处成分分布的影响,发现温度超过1060℃时,晶粒会过度长大,使其矫顽力随之下降。稍低的烧结温度1020-1050℃可以获得Dy分布于晶粒呈＂壳＂状结构并使得Dy尽量分布于晶界处,获得了制备高矫顽力块体稀土永磁较满意的Dy减量化方法。Dysprosium was added to Nd-Fe-B rare earth permanent magnets by DyH3 additions, and a series of （PrNd）30Fe69 B magnets with DyH3 additions and without DyH3 were sintered at different temperatures： 1020,1040, 1050, 1060 and 1080 ~C respectively. The relationship between the remanence （Br）, intrinsic coercivity （ Hcj ）, sintering temperature and microstrueture was investigated. The results showed that Br was higher with high- er sintering temperature due to the magnets reached to fully dense and Hcj was the maximum at sintering temperature 1020 - 1050 ℃. Hcj of the Nd-Fe-B magnets was enhanced efficiently with Dy additions. The grain sizes and the composition distributions in grain and grain boundaries, formed under different sintering temperature, were investi- gated by SEM and EDX. It was shown that the grain grew excessively with higher sintering temperatures, leading to lower Hcj. Rare earth permanent magnets sintered at relatively lower temperatures of 1020 - 1050 ℃were formed a ＂core shell＂ structure and Dy introduced mainly distributed around grain boundaries and grains , which were sug- gested that a novel route to produce high coercive rare earth bulk magnets by employing less expensive heavy rare earth dysprosium to further support clean energy industry development was presented.

关 键 词：镝 钕铁硼 矫顽力 烧结 稀土氢化物 

分 类 号：O482.54[一般工业技术—材料科学与工程]