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Thermal behaviors and structures of three Zr-based binary glass formers, Zr_(50)Cu_(50), Zr_(64)Cu_(36) and Zr_(64)Ni_(36), were investigated and compared using differential scanning calorimetry(DSC), transmission electron microscopy(TEM), high energy X-ray diffraction(XRD) and small angle X-ray scattering(SAXS). The high energy XRD results show that the bulk glass former Zr_(50)Cu_(50) has a denser atomic packing efficiency and reduced mediumrange order than those of marginal glass formers Zr_(64)Cu_(36) and Zr_(64)Ni_(36). Based on TEM observations for the samples after heat treatment at 10 K above their crystallization onset temperatures, the number density of crystals for Zr_(50)Cu_(50) was estimated to be 10~(23)-10~(24) m~(-3), which was four-orders higher than that in Zr_(64)Cu_(36)and Zr_(64)Ni_(36) metallic glasses. SAXS results indicate that Zr_(50)Cu_(50) has higher degree of nanoscale inhomogeneities than those in Zr_(64)Cu_(36) and Zr_(64)Ni_(36) at as-cast state. The observed multiscale structures are discussed in terms of the phase stability and glass-forming ability of Zr-based binary glass formers.
Thermal behaviors and structures of three Zr-based binary glass formers, Zr_ (50) Cu_ (50), Zr_ (64) Cu_ 36 and Zr_ (64) Ni_ 36 were investigated and compared using differential scanning calorimetry High energy X-ray diffraction (SAXS). The high energy XRD results show that the bulk glass former Zr 50 (50) Cu 50 denser atomic packing efficiency and reduced mediumrange order than those of marginal glass formers Zr 64 Cu 36 and Zr 64 Ni 36 based on TEM observations for the samples after heat treatment at 10 K above their K- , the number density of crystals for Zr_ (50) Cu_ (50) was estimated to be 10 ~ (23) -10 ~ (24) m ~ The Cu_ (36) and Zr_ (64) Ni_ (36) metallic glasses have the highest degree of nanoscale inhomogeneities than those of Zr_ (64) Cu_ (36) and Zr_ (64) Ni_ (36) at as-cast state. The obse rved multiscale structures are discussed in terms of the phase stability and glass-forming ability of Zr-based binary glass formers.