烧结钕铁硼制备快淬带性能的研究

Rapidly Quenched NdFeB Permanent Magnet Made from Their Sintered Magnet

采用单辊急冷法熔融NdFeB烧结磁体(工业产品)制取快淬永磁合金。合金薄带具有很高的矫顽力,剩磁比达到0.5以上。合金带经过适当的热处理,可消除制备冷速过高时退磁曲线及磁性能的缺陷。随着烧结磁体磁性能等级提高,其快淬合金的剩磁和最大磁能积均提高,内禀矫顽力下降。由N50烧结磁体制备的快淬合金的较佳性能为:Br=0.84T、Hci=959kA/m、(BH)max=112 kJ/m3。X射线衍射分析表明快淬合金以Nd2Fe14B相晶粒为主,只有少量杂相。

Rapidly quenched NdFeB ribbons were prepared by melt-spun technique with commercial sintered NdFeB hard magnets. The ribbons have very high coercivity values, and the ratios of remnant magnetizations to the saturation values reaches over 0. 5. In case of over-quenched ribbons, annealing treatment can eliminate the distortion of the demagnetization curve and the magnetic properties can therefore be improved. The higher the maximum energy product of the sintered magnets used as raw material, the higher the remnant magnetization and the maximum energy product of the obtained ribbons. The magnetic ribbons made from sintered NdFeB magnet with （BH）m =400kJ/m^3 show following magnetic properties： Br= 0. 84 T, Hci =959 kA/m, （BH）m =112 kJ/m^3 , X-ray diffraction patterns reveal that the rapidly quenched NdFeB ribbons consist of Nd2 Fe14 B as the main phase and some other minor phases.