Effect of the Zr-substitution on the Structural and Magnetic Properties of SmFe10Si2 System

Structural and magnetic characterization of melt-spun ribbons of Sm1-xZrxFe10Si2 (0.1 x 0.6) has been studied using X-ray diffraction and Mössbauer spectroscopy. The formation of the tetragonal ThMn12-type structure has been observed in all alloys, without further annealing. Unit cell parameters are changing gradually with the incorporation of Zr; however, a and c parameters are affected in different degree due to the preference of Zr for RE atomic positions and thus the c/a ratio is increasing. The Curie temperature decreases linearly with Zr substitution from 595 K for x=0.1 to 668 K for x=0.6. The saturation magnetization does not change appreciably in the interval from x=0.1 (123.9 Am2/kg) to x=0.5 (126.0 Am2/kg), but then decreases to 94 Am2/kg for x=0.6. 57Fe Mössbauer Spectroscopy on magnetically aligned samples revealed that Zr introduction affects magnetocrystalline anisotropy.