脉冲磁场技术在高矫顽力稀土永磁测量领域的应用  

Application of pulsed field technique to magnetic property measurements of rare earth based hard magnetic materials with high coercivity

作　　者：林安利[1,2] 贺建[2] 张跃[1] John Dudding 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]中国计量科学研究院磁性测量实验室,北京100013 [3]Hirst Magnetic Instruments Ltd.,Falmouth TRll 4SN,英国

出　　处：《北京科技大学学报》2009年第6期782-787,共6页Journal of University of Science and Technology Beijing

基　　金：国家自然科学基金资助项目(No.10876001);北京市自然科学基金资助项目(No.2082015);国际交流与合作资助项目(No.50620120439,No.2006DFB51000)

摘　　要：简述了超高矫顽力永磁体测量现状,分析了静态磁滞回线仪在测量高矫顽力永磁体时存在的问题及其原因.为解决此问题,采用"f-2f"原理建立了基于脉冲磁场技术的高矫顽力永磁测量装置,该装置能产生最高8 756 kA.m-1的测量磁场,能够测量高矫顽力永磁体的整个磁滞回线.阐述了该脉冲磁场测量装置的优势、组成结构以及涡流修正方法.经过实验验证,该系统具有良好的测量重复性.与国家永磁标准测量装置的对比结果显示:在低矫顽力范围内两者剩磁Br、内禀矫顽力HcJ、磁感应强度矫顽力HcB和最大磁能积(BH)max四个参数的测量偏差在1%以内;在高矫顽力范围,该装置解决了静态磁滞回线仪测量曲线变形的问题.An inherent problem was introduced when measuring the magnetic properties of high coercivity hard magnetic materials with an existent static BH tracer （hysteresisograph） and the reason why the problem happens was discussed. To deal with the problem a pulsed field magnetometer （PFM） system based on the f-2f method, which could generates 8 756 kA· m^-1 magnetic field, was designed and applied to measure the whole hysteresis loop of high coercivity hard magnetic materials. The technical advantages, struc- ture and eddy current effect correction of the system were also introduced. It can be approved, from a large quantity of measurement results, that the long term repeatability of the system is very good. The deviation of magnetic properties, i.e. remanence Br, intrinsic coercivity HeJ, magnetic flux density coercivity HeB, and maximum energy product （BH）max, measured with a PFM compared with that measured with a national standard static BH tracer is within 1% for low coercivity hard magnets. For high coercivity hard magnets the system could measure the whole hysteresis loop and solve the high coercivity problem that a static BH tracer could not avoid.

关 键 词：脉冲磁场 稀土永磁 高矫顽力 磁性测量 退磁曲线 

分 类 号：TB972[一般工业技术—计量学]