Dy_(30)Cu_(70)合金晶界扩散对烧结Nd-Fe-B磁体组织和磁性能的影响  

Effect of Dy_(30)Cu_(70) alloy grain boundary diffusion on microstructure and magnetic properties of sintered Nd-Fe-B magnet

作　　者：饶强 李骞 梁珍葵 吴涛 周锦睿 李忠恺 罗军明[1] 黄有林[1] RAO Qiang;LI Qian;LIANG Zhen-kui;WU Tao;ZHOU Jin-rui;LI Zhong-kai;LUO Jun-ming;HUANG You-lin(School of Materials Science and Engineering,Nanchang Hangkong University,Nanchang 330036,China;School of Aeronautical Manufacturing Engineering,Nanchang Hangkong University,Nanchang 330036,China)

机构地区：[1]南昌航空大学材料科学与工程学院,江西南昌330036 [2]南昌航空大学航空制造工程学院,江西南昌330036

出　　处：《材料热处理学报》2022年第1期61-67,共7页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51401103);江西省重大科技专项(51401103);南昌航空大学三小科技创新课题(2020CL005)。

摘　　要：采用电弧熔炼技术制备了低熔点Dy_(30)Cu_(70)合金,研究了Dy_(30)Cu_(70)合金晶界扩散对烧结Nd-Fe-B磁体磁性能和微观结构的影响。结果表明:烧结Nd-Fe-B磁体与Dy_(30)Cu_(70)粉末在850℃下扩散5 h,然后在450℃下回火0.5 h后,获得的磁体综合性能最佳,其矫顽力、剩磁和最大磁能积分别为1373 kA·m^(-1)、1.32 T和333 kJ·m^(-3),与原始磁体相比,矫顽力增加了21.8%。晶界扩散后,Dy元素会部分取代主相中的Nd元素,形成(Nd,Dy)_(2)Fe_(14)B硬磁相,从而提高磁体的矫顽力,而Cu会改善磁体中富稀土相的结构,减少晶粒间的交换耦合作用。Dy_(30)Cu_(70)晶界扩散后,烧结Nd-Fe-B磁体的热稳定得到一定的提高。Dy_(30)Cu_(70) alloy with low melting point was prepared by arc melting technology,and the effect of grain boundary diffusion of Dy_(30)Cu_(70) alloy on magnetic properties and microstructure of sintered Nd-Fe-B magnet was studied.The results show that the comprehensive properties of the magnet prepared by diffusion at 850℃for 5 h and then tempering at 450℃for 0.5 h using sintered Nd-Fe-B magnet and Dy_(30)Cu_(70) powder as raw materials are the best,and its coercivity,remanence and maximum magnetic energy products are 1373 kA·m^(-1),1.32 T and 333 kJ·m^(-3),respectively.Compared with the as-received magnet,the coercivity increases by 21.8%.After grain boundary diffusion,Dy element will partially replace Nd element in the main phase to form(Nd,Dy)_(2)Fe_(14)B hard magnetic phase,so as to improve the coercivity of the magnet,while Cu will improve the structure of rare earth rich phase in the magnet and reduce the exchange coupling between grains.After Dy_(30)Cu_(70) grain boundary diffusion,the thermal stability of the sintered Nd-Fe-B magnet is improved to a certain extent.

关 键 词：烧结钕铁硼 晶界扩散 低熔点合金 矫顽力 热稳定性 

分 类 号：TG132.2[一般工业技术—材料科学与工程] TM273[金属学及工艺—合金]