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粉末样品的X射线衍射和热磁曲线测量表明,所有的ErFe11-xCoxTi(x=0—11)化合物都结晶ThMn12型结构,且具有良好的单相性.Co替代Fe导致居里温度的显著提高和晶格常数的单调减小,42K下的饱和磁化强度Ms随Co含量的增加在x=3处呈现极大值.ErFe11-xCoxTi化合物当x≤4时,在室温下具有单轴磁晶各向异性,当6≤x≤9时,样品的易磁化方向垂直于c轴,而当x继续增加时,易磁化方向又回到c轴.ErFe11-xCoxTi化合物磁晶各向异性的变化可能与不同过渡族晶位对磁晶各向异性的不同贡献和Co的择优占位有关.通过研究磁化强度与温度的依赖关系(MT)还发现,所有ErFe11-xCoxTi化合物都在居里温度以下的某一温度发生自旋重取向现象.基于磁场取向样品的X射线衍射和磁化强度的温度依赖关系,初步确定了ErFe11-xCoxTi化合物在温度成分平面内的自旋相图
X-ray diffraction and thermomagnetic curve measurements of the powder samples indicate that all of the ErFe11-xCoxTi (x = 0-11) compounds crystallize ThMn12-type structures and have good single-phase properties. The substitution of Co for Fe results in a significant increase of the Curie temperature and the monotonous decrease of the lattice constant. The saturation magnetization Ms at 4 2K shows a maximum value at x = 3 with the increase of Co content. The ErFe11-xCoxTi compound has uniaxial magnetocrystalline anisotropy at room temperature when x ≦ 4, and the magnetization direction of the sample is perpendicular to the c axis when 6 ≦ x ≦ 9, and when x continues to increase, the easy magnetization direction Back to the c axis again. The change of magnetocrystalline anisotropy of ErFe11-xCoxTi compounds may be related to the different contributions of different transitional sites to magnetocrystalline anisotropy and the preferential occupancy of Co. By studying the dependence of magnetization on temperature (MT), it was found that all ErFe11-xCoxTi compounds undergo spin reorientation at a temperature below the Curie temperature. Based on the temperature dependence of X-ray diffraction and magnetization of the magnetic field-oriented samples, the spin-phase diagrams of ErFe11-xCoxTi compounds in the temperature-component plane