Magnetic properties of DyCo10Mo2-xSix compounds

DyCo10Mo2-xSix compounds (x = 0, 0.5, 1.0, 1.5, and 2.0) with the ThMn12 st ructure were prepared by means of arc melting and subsequent vacuum anneali ng. Their magnetic properties were investigated by x-ray diffraction on fix ed aligned powder samples and by magnetization measurements. The lattice co nstants decrease linearly with increasing value of x. The easy-magnetizatio n direction (EMD) of all samples is parallel to the c axis at room temperat ure except for DyCo10Si2 whose EMD is within the basal plane. Deviations of the spontaneous moment up from a linear x dependence are observed. The Cur ie temperature attains a maximum value at x = 1.5. There is a spin reorient ation transition from the easy axis to the easy cone upon cooling for compo unds with x = 0.5, 1, and 1.5. (C) 1999 American Institute of Physics. [S00 21-8979(99)01618-7].