应用MFT分析R_2Fe_(17-x)M_x(R=Pr,Nd;x=0.2;M=Al,Ga)合金的磁性

Analysis of the Magnetic Behaviors of R 2Fe 17- x M x (R=Pr,Nd; x =0.2;M=Al,Ga) Alloys by MFT

用两亚点阵ＭＦＴ分析了Ｒ２Ｆｅ１７－ｘＭｘ合金的饱和磁化强度与温度的关系。得到了分子场系数ｎＲＲ、ｎＲＦ和ｎＦＦ，计算出了居里温度，给出了分子场ＨＲ（Ｔ）、ＨＦｅ（Ｔ）与温度的关系曲线。计算结果表明，在Ｒ２Ｆｅ１７中用Ａｌ、Ｇａ替代部分Ｆｅ离子后，分子场系数ｎＦＦ明显增大，除Ｐｒ２Ｆｅ１７的ＨＲ（Ｔ）外。

The temperatrue dependence of the saturation magnetization of R 2Fe 17- x M x alloys has been analysed by the two-sublattice molecular field theory.The molecular field coefficients n RR , n RF and n FF are obtained.Curie temperatures of the alloys are calculated.The curves of the intensity of molecular field H R( T ) and H Fe ( T ) are also plotted.The results of analysis showed that the coefficient n FF increases after the substitution of Al(or Ga)atoms for Fe in R 2Fe 17 and except H R( T ) of Pr 2Fe 17 the H R( T ) and H Fe ( T )markedly increase in a large temperature range.