论文部分内容阅读
Structure, magnetic properties and magnetostriction of Sm0.9Pr0.1(Fe1-xCox)2 compounds have been investigated by means of X-ray diffraction, a.c. initial susceptibility, extracting sample magnetometer, Mossbauer spec-troscopy and standard strain gauge techniques. The lattice parameter a of the MgCu2-type Laves compounds Sm0.9Pr0.1(Fe1-xCox)2 decreases nonlinearly with increasing Co concentration, deviating from the Vegard’s law. Curie temperature Tc increases initially from 668 K for x=0 to 694 K for x=0.2 and then decreases to 200 K for x=1.0. The saturation magnetization Ms at temperatures 1.5 K, 77 K and 300 K have the same variation tendency as the composition dependence of Curie temperature, in consistence with rigid-band model. The easy magnetization direction (EMD) of Sm0.9Pr0.1(Fe1-xCox)2 lies along [111] direction in the range x<0.6, and changes to [110] for x=0.8, while Sm0.9Pr0.1Co2 stays in the paramagnetic state at room temperature. The composition dependence of the average hyperfine field,Hhf ,
Structure, magnetic properties and magnetostriction of Sm0.9Pr0.1 (Fe1-xCox) 2 compounds have been investigated by means of X-ray diffraction, ac initial susceptibility, extracting sample magnetometer, Mossbauer spec- troscopy and standard strain gauge techniques. The lattice parameter a of the MgCu2-type Laves compounds Sm0.9Pr0.1 (Fe1-xCox) 2 decreases nonlinearly with increasing Co concentration, deviating from the Vegard’s law. Curie temperature Tc increases initially from 668 K for x = 0 to 694 K for x = 0.2 and then decreases to 200 K for x = 1.0. The saturation magnetization Ms at temperatures 1.5 K, 77 K and 300 K have the same variation tendency as the composition dependence of Curie temperature, consistence with rigid-band model. The easy magnetization direction (EMD) of Sm0.9Pr0.1 (Fe1-xCox) 2 lies along [111] direction in the range x <0.6, and changes to [110] for x = 0.8, while Sm0.9Pr0.1Co2 stays in the paramagnetic state at room temperature. The composition dependence of the averag e hyperfine field, Hhf,