摘要
利用X射线衍射仪(XRD)、振动样品磁强计(VSM)、透射电子显微镜(TEM)和三维原子探针(3DAP)等研究了Nb元素对纳米晶复合Nd_(9.5)Fe_(79-x)Co_5Nb_xB_(6.5)(x=0,1,2,3)永磁合金微结构和磁性能的影响。结果表明,随着Nb元素的增加,合金的剩磁J _r首先增加,在Nb含量为1 at%时达到最大值0.94 T,继续增加Nb元素后,合金的剩磁开始下降;矫顽力_i H_c则随着Nb元素的增加逐步增加,当Nb含量超过2 at%后,增加幅度变缓;合金的最大磁能积(BH)_(max)随着Nb元素的增加先增加后降低,纳米晶复合Nd_(9.5)Fe_(79-x)Co_5Nb_xB_(6.5)合金具有最优的综合磁性能,即J_r=0.91 T,_i H_c=663k A/m,(BH)_(max)=120 k J/m^3。Nb元素在合金的晶化过程中富集于晶间形成Nb Fe B相,有利于细化晶粒尺寸,从而提高合金的磁性能。
Nanocomposite Nd_（9.5）Fe_（79-x）Co_5Nb_xB_（6.5）（x=0, 1, 2, 3） alloys were prepared by melt-spinning at a rate of 18 m/s cooperating with subsequent annealing. The effects of Nb content on microstructure and magnetic properties for the alloys have been studied by XRD, VSM,TEM and 3DAP. The results show that the J_r firstly increases with the increasing of Nb content from 0.92 T up to 0.94 T at x=1, and then decreases obviously with further Nb addition. The _i H_cincreases monotonically and then increases at a lower rate when the Nb content exceeds 2at%. The（BH）max appears to increase from 104 k J/m3 at x=0 to a maximum of 120 k J/m3 at x=2, and then decreases sharply. An intergranular Nb Fe B phase with chemical composition near the Nb：Fe：B stoichiometry of 26： 48： 26 between the Nd_2Fe_（14） B interfaces is found in Nd_（9.5）Fe_（79-x）Co_5Nb_xB_（6.5） by the 3DAP technique, which provides direct evidence of magnetic properties improvement.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2017年第1期122-126,共5页
Rare Metal Materials and Engineering
基金
上海市青年科技启明星计划(14QB1403300)
关键词
纳米复合
NDFEB
微结构
磁性能
永磁合金
nanocomposite
NdFeB
microstructure
magnetic properties
permanent alloys
