摘要
采用放电等离子烧结技术制备了新型NdFeB磁体,研究了烧结工艺和热处理工艺对磁体的磁特性、尺寸精度及致密度的影响。同时利用B-H回线仪、扫描电子显微镜对其磁特性、显微组织结构进行了分析测试。结果表明,这种新型的烧结NdFeB磁体具有独特的显微组织结构,主相Nd2Fe14B晶粒细小、尺寸均匀,富钕相弥散分布在主相边界上。获得最佳工艺条件下制备的磁体的磁特性为:最大磁能积(BHmax)240kJ/m3,内禀矫顽力(Hci)1160kA/m,磁体的密度达到7.58g/cm3,接近材料的理论密度,同时磁体的尺寸精度达到20μm。
NdFeB magnet was prepared by spark plasma sintering technique. Effects of sintering process and heat treatment on the magnetic properties, dimensional precision as well as density were studied. Magnetic properties, microstructure and constituents were investigated by means of B- H loop- line instrument, SEM. It is found that the microstructure of SPS NdFeB magnet is quite different, the grain size of Nd2Fe14B is fine and uniform while the distribution of the Nd- rich phase is heterogeneous. The optimal magnetic properties of the SPS NdFeB magnet obtained so far are of a maximum energy product of 240 kJ/m3, a coercive force of 1160 kA/m. The density of the magnet reaches 7.58 g/cm3 as well as the dimensional precision of the magnets is about 20μ m.
出处
《功能材料与器件学报》
CAS
CSCD
2003年第3期295-299,共5页
Journal of Functional Materials and Devices
