Magnetic properties of Sm2Fe17−xSix and Sm2Fe17−xSixC compounds

Abstract

Iron-rich intermetallic compounds Sm2Fe17−xSix and Sm2Fe17−xSixC (x=0, 1, 2, and 3) were studied. The as-prepared compounds are single phase with the rhombohedral Th2Zn17-type structure except for Sm2Fe17C and Sm2Fe16SiC which contain some amounts of α-Fe. The unit cell volumes and saturation magnetization at room temperature are found to decrease linearly with increasing Si concentration x. The Curie temperature Tc is found first to increase and then to decrease with increasing Si content. X-ray diffraction measurements on magnetically aligned powder samples show that the easy magnetization direction of the Sm2Fe17−xSix samples with x≤2 is planar while that of the sample with x=3 is conical. The Sm2Fe17−xSixC samples with x≤3 exhibit an easy c-axis anisotropy at room temperature. The anisotropy field is 83 kOe for x=0 and it rises to 110 kOe at x=1, and then drops with increasing Si concentration to 55 kOe at x=3.