Enhancement of glass-forming ability of FeGaPCB bulk glassy alloy with high saturation magnetization

The effect of Mo and Si additions on the glass-forming ability (GFA) of Fe–Mo–Ga–P–C–B–Si alloys was investigated. The addition of 2 at% Mo combined with 2 at% Si was found to be effective for the extension of the supercooled liquid region (ΔTx) defined by the difference between glass transition temperature (Tg) and crystallization temperature (Tx). The ΔTx value is 26 K for the Fe78Ga2P12C4B4 alloy, and increases to 52 K for the Fe76Mo2Ga2P10C4B4Si2 glassy alloy. In addition, this glassy alloy exhibits a highly reduced glass transition temperature (Tg/Tl) of 0.59. Large ΔTx and high Tg/Tl enabled us to prepare the Fe76Mo2Ga2P10C4B4Si2 bulk glassy alloy successfully with a diameter of 2 mm and with a high saturation magnetization (Is) of 1.32 T. The Fe76Mo2Ga2P10C4B4Si2 glassy alloy also exhibits good soft magnetic properties, i.e., high effective permeability at 1 kHz of 9700 and low coercive force of 3 A/m.