Analysis of the Structural, Thermal, and Magnetic Properties in the Bulk Metallic Glass Alloy Co36Fe36B19.2Si4.8Nb4 System

Abstract

The metallic glass {(Fe1-xCox)(0.75) B0.2Si0.05}(96)Nb-4 (x = 0 similar to 0.9) system was studied. One of these systems, {Fe1-xCox)(0.75) B0.2Si0.05}(96)Nb-4 (x = 0.5), has the highest glass-forming ability (GFA). We made Co36Fe36B19.2Si4.8Nb4 into ribbon with a thickness of 0.03 mm, strips with thicknesses of 1 mm, 2 mm, and 3 mm and rods with diameters of 2 mm and 3 mm by melt spinning and injection casting. X-ray diffraction (XRD) and differential scanning calorimeter (DSC) studies showed the cast strips to be fully amorphous up to a thickness of 2 mm. The thermal stability parameters, such as supercooled liquid region (Delta T-x = T-g - T-x) and glass transition enthalpy (Delta H), were measured by using a differential scanning calorimeter to be 41.6 - 45.3 K and 1.2169 - 3.7031 J/g, respectively. The bulk glassy alloys also exhibit soft-magnetic properties in ribbons and semi-hard magnetic properties in thicker samples, i.e., a high saturation magnetization of 0.94 - 1.11 T and a coercive force of 27.9 - 7162 A/m.