Fe-Based Ferromagnetic Glassy Alloys with Wide Supercooled Liquid Region

Abstract

A multicomponent Fe72Al5Ga2P11C6B4 alloy was found to form a glassy phase with a wide supercooled liquid region before crystallization and of ferromagnetism at room temperature. The glass transition temperature (Tg), crystallization temperature (Tx) and temperature intervals of supercooled liquid, ΔTx(=Tx−Tg) for the glassy alloy are 732, 793 and 61 K, respectively. It is to be noticed that the supercooled liquid region exceeds 60 K which is about 3 times larger than the largest ΔTx value for the Fe-based glassy alloys reported up to date. The amorphous alloy also exhibits good bending ductility and rather good soft ferromagnetic properties at room temperature. The soft magnetic properties are improved by annealing at temperatures above the Curie temperature (Tc). The magnetic properties at room temperature for the glassy alloy annealed for 600 s at 723 K are 605 K for Tc, 1.07 T for saturation magnetization, 5.1 A/m for coercivity, 9000 for permeability at 1 kHz and 2.0×10−6 for magnetostriction. The finding of the ductile Fe-based glassy alloy exhibiting simultaneously the wide supercooled liquid region and good soft ferromagnetic properties is expected to create a new ferromagnetic bulk material with good deformability.