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Abstract: The glass formability, magnetic properties and thermal stability of the Y–Fe–B–M bulk metals (M=Al, Hf, Nb, Ta, and Ti) alloys have been investigated. For (Y0.06Fe0.72B0.22)98M2 series alloys, Al or Hf addition deteriorates the glass forming ability (GFA), but Nb or Ta addition broadens supercooled region from 50.2°C for ternary rod to 61.5°C for M=Ta and 62°C for M=Nb, respectively. The bulk glassy rod as large as 3mm in diameter can be obtained. However, their magnetization and Curie temperature are reduced due to the magnetic dilution by the addition of these nonmagnetic elements. On the other hand, for Y4Fe72B22M2 series alloys, almost all the substitution elements, except Al, can improve GFA of alloy rod, making the diameter of bulk glassy rod as large as 3mm for Ti or Hf substitution and 4mm for Ta or Nb substitution, respectively. It is arisen from the further expansion of the supercooled region to 70.4–84.2°C. In this study, Y4Fe72B22Ta2 amorphous rod displays the optimal glass forming ability and also good soft magnetic properties of σ s =123emu/g, H c =0.2Oe, and T C =276°C. [Copyright &y& Elsevier]

Abstract: The Ti effect on the glass forming ability and the magnetic properties of Y–Fe–B–Ti bulk metallic glasses have been investigated. Substituting 2 and 4at.% Ti for Fe or B in Y6Fe72B22 alloy decreases the saturation magnetization (σ s) and deteriorates the glass forming ability, respectively. However, substitution of 2at.% Ti for Y in Y6Fe72B22 alloy induces larger supercooled region of 72.7°C, which not only makes the bulk glassy rod as large as 3mm in diameter, but also results in the superior soft magnetic properties of σ s =126emu/g, coercivity (H c)=0.2Oe and Curie temperature (T C)=268°C. Among all Y–Fe–B–Ti bulk amorphous rods, Y4Fe72B22Ti2 displays the best glass forming ability and also the proper soft-magnetic properties. [Copyright &y& Elsevier]

Abstract: The amorphous alloy rods of (Zr53Cu30Ni9Al8)100−x Six (x =0.25, 0.5, 0.75, 1) with a diameter of 2–6mm were prepared by drop casting method in an Ar atmosphere. The thermal properties, including glass forming ability (GFA) and thermal stability during isothermal annealing of these amorphous alloys, and the mechanical properties have been systematic investigated by the combination of DSC, XRD, SEM, TEM, and compression test. The result of X-ray diffraction reveals that these entire (Zr53Cu30Ni9Al8)100−x Si x alloy rods exhibit a typical amorphous diffraction pattern with only a broad maximum around 2θ around 40 degree. Both T g (glass transition temperature) and T x (crystallization temperature) of these (Zr53Cu30Ni9Al8)100−x Si x alloys increase with the silicon addition. In addition, both the activation energy of crystallization and the incubation time of isothermal annealing these (Zr53Cu30Ni9Al8)100−x Si x amorphous alloys indicate that the (Zr53Cu30Ni9Al8)99.25Si0.75 alloy possesses the best thermal stability in the (Zr53Cu30Ni9Al8)100−x Si x alloy system. In parallel, the result of compression test shows that the yield strength increases with the addition of Si content and reaches to a maximum value about 1750MPa with 3% plastic strain for the (Zr53Cu30Ni9Al8)99.25Si0.75 amorphous alloy. [Copyright &y& Elsevier]