熔体过热对Nd9Fe70Ti4C2B15快淬薄带组织演化和磁性能的影响  

Effects of Melt Overheating on Microstructure Evolution and Magnetic Properties of Nd9Fe70Ti4C2B15 Melt-spun Ribbons

作　　者：董鸣月 潘晶[1] 刘新才[1] 徐山雪 赵丽 DONG Ming-yue;PAN Jing;LIU Xin-cai;XU Shan-xue;ZHAO Li(Faculty of Materials Science and Chemical Engineering,N ingbo University,Ningbo 315211,China)

机构地区：[1]宁波大学材料科学与化学工程学院

出　　处：《稀土》2018年第5期24-31,共8页Chinese Rare Earths

基　　金：国家自然科学基金项目(51174121,51274125);浙江省重点科技创新团队项目(2012R10016-08);宁波大学王宽诚幸福基金项目资助

摘　　要：在不同的熔体过热温度T＋（T＋=1565 K,1585 K,1625 K）下制备了Nd9Fe70Ti4C2B15合金快淬薄带（辊速为10 m·s^-1）,研究了薄带的微观组织及其磁性能随T＋提高而发生的变化。结果表明,快淬组织中的非晶含量随着T＋提高而明显增大,T＋为1625 K的快淬组织呈现出完全非晶结构。快淬组织的结构差异导致其退火所得Nd2Fe14B,Fe3B和α-Fe的纳米复合组织的晶粒尺寸和硬磁性相含量明显地不同。随着T＋从1565 K提高到1625 K,纳米复合组织的平均晶粒尺寸增大了约8 nm,并且Nd2Fe14B相在复合组织中的相对含量减小了约5%-6%,这导致退火薄带的磁性能随之下降。经过1080 K×5 min退火后,T＋为1565 K的快淬薄带获得了最佳综合磁性能：Hci=720.68 k A·m^-1,Br=0.74 T,（BH）max=72.03 k J·m^-3。A series of Nd9Fe70Ti4C2B15 melt-spun ribbons were prepared by rapid quenching at different melt overheating temperatures（T＋= 1565 K,1585 K and 1625 K） with the roller surface speed of 10 m·s^-1,and the changes of both their microstructures and magnetic properties with the increase of T＋were investigated. The results showed that the amorphous content in the as-quenched ribbons significantly increased with increasing T＋,and the complete amorphous structure appeared when T＋was raised to 1625 K. The deference in their microstructures of the as-quenched ribbons resulted in the obvious distinctions in their grain sizes and hard magnetic phase contents of the annealed Nd2Fe14B,Fe3B and α-Fe nanocomposites. With increasing T＋from 1565 K to 1625 K,the average grain size of annealed nanocomposites increased by about 8 nm,and the relative content of Nd2 Fe14 B phase in them decreased by 5% - 6%,which led to the deterioration of the magnetic properties of the annealed ribbons. The optimal comprehensive magnetic properties,Hci= 720. 68 k A·m-1,Br= 0. 74 T,（BH）max= 72. 03 k J·m^-3 were achieved for the ribbon melt-spun at T＋= 1565 K to be annealed at 1080 K for 5 min.

关 键 词：熔体过热 稀土永磁合金 快淬薄带 纳米复合组织 磁性能 

分 类 号：TM273[一般工业技术—材料科学与工程] TG322[电气工程—电工理论与新技术]