2001 Volume 42 Issue 6 Pages 1052-1055
The effect of Co on the magnetic properties and glass-forming ability for the Fe78−xCoxGa2P12C4B4 glassy alloys was investigated. The addition of 4 to 8 at%Co was found to be effective for the extension of the supercooled liquid region (ΔTx) defined by the difference between the glass transition temperature (Tg) and crystallization temperature (Tx). The ΔTx value is 26 K for the Fe78Ga2P12C4B4 alloy and increases to 37 K for the 4 at%Co alloy. Besides, the addition of a small amount of Co was also found to be effective for increasing the saturation magnetization (Is) and decreasing the coercive force (Hc). These glassy ribbon alloys exhibit good soft magnetic properties of 1.36 to 1.43 T for saturation magnetization and 1.5 to 1.8 A/m for coercive force. The largest saturation magnetization (Is) is 1.43 T for Fe74Co4Ga2P12C4B4 alloy. Based on its large ΔTx, we tried to prepare bulk glassy Fe74Co4Ga2P12C4B4 rods in a cylindrical form with different diameters. The glassy single phase was obtained in the diameter of 0.5 and 1.0 mm. These bulk glassy alloys also exhibit high saturation magnetization of about 1.42 T.