Thermal stability and magnetic properties of (Fe, Co)-Zr-Nd-B amorphous alloys

A new type of Fe-based amorphous alloy containing rare earth element was prepared by melt spinning technique. The glass-forming ability (GFA), thermal stability and magnetic properties were investigated in the composition range of Fe70Co8Zr7-xNdxB15(x =0% to 6%, atom fraction). They exhibit the glass transition and supercooled liquid region before crystallization. The width of supercooled liquid region obtained for the series of Fe70Co8Zr7-xNdxB15 exceeds 40 K, among which the maximum width for Fe70Co8Zr5Nd2B15 amorphous alloy reaches 61 K. Another main attraction is that the selected Fe-based amorphous alloys have good soft magnetic properties. The saturation magnetization ( J(s)) is in the range of 1.10 to 1.37 T, and coercive force (H-c) in the range of 2.28 to 8.15 A.m(-1) for Fe70Co8Zr7-xNdxB15 amorphous alloys. It is found that the saturation magnetization (J(s)) increases with the increment of the relative content of the Nd for the Fe70Co8Zr7-xNdxB15 alloys. The H-c values for the glasses with Nd content of 1%, 2% and 3% are below 3 A.m(-1). The research indicates that Fe70Co8Zr5Nd2B15 amorphous alloy has good high GFA and good soft magnetic properties, of which the width of supercooled liquid region, J(s), and H-c are 61 K, 1.25 T and 2.28 A.m(-1), respectively.