Fecobsinb Department Of Soft Magnetic Bulk Amorphous Alloy Formation And Performance

Multi-component bulk FeCoBSiNbRe(Re=Dy,Tb) bulk amorphous alloys were prepared by means of copper-mold vacuum suction casting. The glass forming ability (GFA), thermal stability and soft magnatic properties of these alloys were investigated by differential scanning calorimeter (DSC), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The main results obtained are summarized as follows.1) (Fe_0.5Co_0.5)_<sub>72B_19.2Si_4.8Nb₄ amorphous alloy rod with a diameter of 2mm have been prepared. After adding 2at% Dy and Tb, the maximum diameter for [(Fe_0.5Co_0.5)_0.72B_0.192Si_0.048Nb_0.04]₉₈Re₂ amorphous alloy rods is 3mm.2) As the content of iron element increases, the GFA of [(Fe_1-XCo_X)_0.72B_0.192 Si_0.048Nb_0.04]₉₈Dy₂ alloy will decrease. When the ratio of iron and cobalt (Fe/Co) increases from 5:5 to 9:1, some amount of crystal phase will appear in the alloy with a diameter of 2mm. In (Fe_1-XCo_X)_0.72B_0.192Si_0.048Nb_0.04]₉₈Tb₂ alloy, when the ratio of Fe and Co is 8:2, crystal phase will occur.3) The glass transition temperature (Tg), the onset temperature of crystallization (Tx) and the supercooled liquid region (ATx) for (Fe_0.5Co_0.5)₇₂B_19.2Si_4.8Nb₄ bulk amorphous alloy are 574℃, 627℃ and 65℃, respectively. After adding 2at% Dy and Tb, Δ Tx for the [(Fe_0.5Co_0.5)_0.72B_0.192Si_0.048Nb_0.04]₉₈Dy₂ and [(Fe_0.5Co_0.5)_0.72B_0.192Si_0.048Nb_0.04]₉₈Tb₂ bulk amorphous alloy is 78 ℃ and 72 ℃, respectively.4) In the [(Fe_1-XCo_X)_0.72B_0.192Si_0.048Nb_0.04]₉₈Dy₂ bulk amorphous alloys, when Fe/Co ratio increases from 5:5 to 8:2, the ATx drop from 78℃ to 51 ℃. Similarly, the ΔTx for [(Fe_1-XCo_X)_0.72B_0.192Si_0.048Nb_0.04]₉₈Tb₂ bulk amorphous alloys drops from 72℃ to 62℃ when the Fe/Co ratio increases from 5:5 to 7:3.5) The magnetization intensity (Ms) of the (Fe_0.5Co_0.5)₇₂B_19.2Si_4.8Nb₄ alloy with a diameter of 2mm is 77.47emu/g. After adding 2at% Dy and Tb. Ms for the new amorphous alloys with 3mm diameter is 53.51emu/g and 62.34emu/g, respectively.6) When Fe/Co ratio increases from 5:5 to 8:2, the magnetization intensity, Ms, of [(Fe_1-XCo_X)_0.72B_0.192Si_0.048Nb_0.04]₉₈Dy₂ amorphous alloys also increases from 53.51emu/g to 81.47emu/g. And for [(Fe_1-XCo_X)_0.72B_0.192Si_0.048Nb_0.04]₉₈Tb₂ amorphous alloys, when Fe/Co ratio increases from 5:5 to 7:3, the Ms will increase from 62.34emu/g to 78.30 emu/g. For both [(Feo.9Coo.i)o.72Bo.i92Sio.o48Nb0.o4]98Dy2 and [(FeosCoo 2)0 72Boi92Sio.o48Nboo4]98Tb2 alloys containing some crystalline phase, Ms is 104.23 emu/g and 82.66emu/g, respectively.