Novel tin-containing Fe-base glassy alloys

The structure and magnetic properties of melt-spun multicomponent Fe_80-xSn_xP₁₂Si₄B₄ (x=1∼8 at%) ribbons were investigated. The improvement of thermal stability was recognized with the replacement of Fe by 1∼6 at% Sn in these alloys. The supercooled liquid region (ΔT_x) defined by the difference between crystallization temperature and glass transition temperature increases from 38.4 K as x=1 to 46.6 K as x=6. Optimal magnetic properties of Fe_80-xSn_xP₁₂Si₄B₄ (x=1∼6 at%) amorphous ribbons annealed at 723 K for 600 s are: saturation magnetization 1.33 T; coercive force 2.86 A/m, maximum permeability 134 000, core loss 0.07 W/kg (50 Hz, 1 T external magnetic field); Curie temperature is from 593 K to 600 K; the resistivity spans from 154 to 188 μΩ-cm. The alloys have potential in applications such as cores for power transformers.