电弧炉制备的Sm2Fe17-xCrx化合物的结构与磁性

通过X射线衍射、磁测量等手段对电弧炉制备的不同热处理条件的Sm₂Fe_17-xCr_x（x=1—3）化合物的结构和磁性进行了研究.结果表明1050 ℃下退火5 d的Sm₂Fe_17-xCr_x（x=1—3）化合物具有菱方相的Th₂Zn₁₇型结构，同样温度下退 关键词： 2Fe_17-xCr_x化合物')" href="#">Sm₂Fe_17-xCr_x化合物 磁体积效应 居里温度 磁晶各向异性

Structure and magnetic properties of Sm2Fe17-xCrxcompound prepared by arc melting

The structural and magnetic properties of Sm₂Fe_17-xCr_x compound have been investigated by means of x-ray diffraction and magnetization measurements. The results show that the Sm₂Fe_17-xCr_x （x=1—3） compounds annealed at 1050 ℃ for 5 days have a rhomhedral Th₂Zn₁₇-type structure，and the Sm₂Fe_17-xCr_x（x=25, 30） compounds annealed at 1050 ℃ for 7 days have a monoclinic Nd₃（Fe，Ti）₂₉-type structure. Long annealing time and high content of Cr can make the Sm-Fe-Cr compound with a Nd₃（Fe，Ti）₂₉-type structure become very stable. This is quiet different from the R₂Fe_17-xCr_x compound （R is a heavy rare earth element）. The analysis of unit-cell volume and unit-cell parameters show that there exists a strong anisotropic magneto-volume effect in Sm₂Fe_17-xCr_x compounds. The result of magnetization measurement shows that the effects of the substituting Cr for Fe at dumbbell sites on the Curie temperature and the magneto-crystalline anisotropy of the compound with Th₂Ni₁₇-type structure are greater than that of the compound with Th₂Zn₁₇-type structure.