热变形工艺对各向异性NdFeB永磁体显微结构和磁性能的影响  

Effects of hot deforming on the microstructure and magnetic properties of anisotropic permanent NdFeB magnets

作　　者：雷颖劼[1] 刘颖[1] 李军[1] 

机构地区：[1]四川大学材料科学与工程学院,四川成都610065

出　　处：《磁性材料及器件》2013年第4期5-8,60,共5页Journal of Magnetic Materials and Devices

基　　金：国家863计划资助项目(2011AA03A403);四川省科技支撑计划资助项目(2013GZ0056;2011GZ0117)

摘　　要：采用热压-热变形法制备各向异性NdFeB磁体,通过正交实验研究了热变形温度、变形量以及变形速率对磁体磁性能及显微结构的影响。结果表明,随变形温度、变形量、变形速率的增高增大,磁体剩磁Br及最大磁能积(BH)max增高,当变形温度升高至700℃、变形量增大到65%、以0.045mm/s的速率变形时,磁体获得最佳磁性能,(BH)max达360kJ/m3(45MGOe),同时主相NdFeB晶粒由最初的球状晶、沿垂直于压力方向长大转变为片状晶,晶粒取向度增高;当变形温度、变形量过高或变形速率过低时,磁体中将会出现异常长大晶粒,使磁性能恶化。Anisotropic NdFeB magnets have been prepared by hot-pressing/hot-deforming. Orthogonal experimental method was utilized to investigate the effect of temperature, degree and rate of deformation on the microstructure and magnetic properties of the magnets. The result shows that with increasing hot deforming temperature, degree rate, the mallets＇ Br and （BH）max improve. At deforming temperature of 700℃, rate of 0.045mm/s and degree of 65%, the hot deformed magnet was prepared with optimal （BH）max of 360kJ/m^3 （45MGOe）. The morphology of main phase grains transform from sphere to flake, and the alignment degree of enhances. For too high deforming temperature, degree or too low d,eforming rate, abnormal growth of the grain occurs, resulting in deterioration of magnetic properties.

关 键 词：NDFEB磁体 热变形 正交实验 磁性能 微观结构 

分 类 号：TM273[一般工业技术—材料科学与工程]