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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 thermal plastic deformation behavior of the (Zr53Cu30Ni9Al8)99.5Si0.5 bulk metallic glass (BMG) was studied by means of thermo mechanical analysis (TMA) and high-temperature compression test in the supercooled liquid region. Using the result obtained from TMA, the deformation behavior for (Zr53Cu30Ni9Al8)99.5Si0.5 BMG rod was investigated by compression test at different strain rates (5×10−3∼5×10−1 s−1) and temperatures in the supercooled liquid region, specifically at 733K, 738K, 743K, 748K, and 753K. The value of flow stress with a constant strain rate of 5×10−3 s−1 decreases with increasing temperature and reaches a relatively low flow stress of 36MPa at the test temperature of 753K. Conversely, the value of flow stress increases with the strain rate in compression. In this paper, an imprinted hologram pattern with 0.6μm depth was demonstrated which showed extremely good microforming ability of this (Zr53Cu30Ni9Al8)99.5Si0.5 BMG in the supercooled liquid region. [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]