Abstract
Structural and soft magnetic properties of (Fe1-xSix)-Hf-C films (0 ≤ x ≤ 0.27) crystallized from amorphous state were investigated as functions of Si concentration. They crystallize as nanocrystalline in which ultrafine HfC particles are dispersed. Most of the Si in the films is dissolved in bcc-Fe after crystallization. By increasing the Si concentration to x= 0.13, the thermal stability of the soft magnetic properties becomes 50 K higher than that of the Fe-Hf-C films. Moreover, high frequency permeability has been improved owing to the increase in electrical resistivity by 4 to 5 fold. Sufficiently high saturation magnetization of 1.3 T was obtained even when x is 0.13. For the films with x larger than 0.15, good soft magnetic properties could not be obtained probably because of the stress induced anisotropy and the coexistence of an amorphous phase with low Curie temperature.
