Contribution of the crystalline phase Fe/sub 100-x/Si/sub x/ to the temperature dependence of magnetic properties of FINEMET-type alloys

The temperature dependence of the hysteresis loop, saturation magnetization, and saturation magnetostriction of rapidly quenched ribbons of the compositions Fe/sub 100-x/Si/sub x/ (x=12.1, 13.8, 20.0) and of FINEMET-type material with compositions Fe/sub 73.6/Cu/sub 1/Nb/sub 3/Si/sub 13.5/B/sub 9/ Fe/sub 73.5/Cu/sub 1/Nb/sub 3/Si/sub 16.5/B/sub 6/ were measured between room temperature and 400/spl deg/C. This paper analyzes the temperature dependence of the saturation magnetostriction and the saturation magnetization of the FINEMET ribbons after various heat treatments, assuming a superposition of the properties of the nanocrystalline Fe-Si and of the remaining amorphous phase. The behavior of the coercivity of Fe-Si prepared by rapid solidification follows roughly that of the (absolute value) of the magnetostriction. The Curie temperature of the remaining amorphous phase is enhanced.