Nd_(3-x)Pr_xFe_(27.7)Ti_(1.3)化合物的结构与磁性研究

Structure and Magnetic Properties of Nd_(3-x)Pr_xFe_(27.7)Ti_(1.3) Compounds

制备并研究了Nd_3(Fe,Ti)_(29)型永磁材料Nd_(3-x)Pr_xFe_(27.7)Ti_(1.3)系列化合物的结构与磁性.结果显示:Nd_(3-x)Pr_xFe_(27.7)Ti_(1.3)系列化合物在0≤x≤2.5范围内依然保持单斜晶系Nd_3(Fe,Ti)_(29)型结构,空间群为A2/m;晶胞体积和晶格常数随着Pr含量x的增减略有增大;从x=0.5开始,该系列化合物由面各向异性转变为轴各向异性,当x=2.5时又转变为面各向异性;化合物的各向异性场Ba随着Pr含量的增加而先增后减;在不同温度条件下化合物的饱和磁化强度Ms的总体趋势是先增后减,但在x=0.5和x=1.0处出现突然增大和减小现象;居里温度的变化为先增后减,但在x=1.5和x=2.5时明显小于其他组分的化合物.

The Nd3（Fe,Ti）29 type Nd3-xPrxFe27.7Ti1.3compound were prepared and their structural and magnetic properties were investigated.It is found that the Nd3-xPrxFe27.7Ti1.3 compounds with Pr concentration of 0≤x≤2.5 keep the monoclinic symmetry with the space group A2/m.The volume and lattice parameters slightly increase with the increasing Pr concentration.A easy plane to easy axial anisotropy transition was observed in the compounds with x〉0.5,while a easy plane anisotropy was found for the compound with x=2.5.The anisotropy field Baincreases with the Pr concentration up to x=0.2,and then decreases.The saturation magnetization Msof the compounds increases first and then decreases with the increasing substitution concentration.Whereas,sudden increase of Msat x=0.5 or decrease at x=1.0 was also observed.The Curie temperature TC of the compounds increases for lower concentration and decreases for higher concentration,and the compounds with x=1.5 and 2.5 having much lower TC.