Synthesis of ferromagnetic Fe-based bulk glassy alloys in the Fe-Nb-B-Y system

The effect of substitution of Y for Fe on the glass forming ability (GFA), magnetic and mechanical property has been studied in Fe77-xNb6B17Yx (x = 0-4) alloys. Replacement of 1-4at.% Fe by Y increased the thermal stability of the glass and liquid phase in the Fe-Nb-B-Y alloys. It was found that the Fe74Nb6B17Y3 alloy exhibited the largest T-rg (0.60) and gamma (= T-x/[T-g + T-L])(0.396) values enabling the fabrication of bulk metallic glass (BMG) with a diameter of up to 2 mm. The BMG alloy (greater than or equal to 74 at.% Fe) exhibited high compressive fracture strength and hardness of about 3 GPa and 1060 Hv, respectively. The partial replacement of 3 at.% Fe by Y in Fe-Nb-Y-B improved the alloy magnetization saturation by about 10%. (C) 2004 Elsevier B.V. All rights reserved.