Phase redistribution in an in situ Mg-based bulk metallic glass composite during deformation in the supercooled liquid region

An In-situ Mg-based bulk metallic glass (BMG) composite containing 40% volume fraction of Mg-rich crystalline flakes was produced by die casting. During cooling from the melt, the flakes nucleate heterogeneously and subsequently grow with their broad faces parallel to the {0001} plane. This generated a uniform dispersion of randomly-oriented flakes within an amorphous matrix. When compressed uniaxially up to 60% reduction in the supercooled liquid (SCL) region, the flakes in this composite were substantially aligned their broad faces towards the compression plane that generated a strong //ND fibre texture.

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Quasi-static and dynamic deformation of an in-situ Ti-based metallic glass composite in supercooled liquid region

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2016.04.062 ◽

2016 ◽

Vol 679 ◽

pp. 239-246 ◽

Cited By ~ 8

Author(s):

J. Bai ◽

J.S. Li ◽

J. Wang ◽

X. Xie ◽

R. Feng ◽

...

Keyword(s):

Metallic Glass ◽

Dynamic Deformation ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Liquid Region ◽

Glass Composite

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Homogeneous Flow of In Situ Bulk Metallic Glass Matrix Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.551-552.561 ◽

2007 ◽

Vol 551-552 ◽

pp. 561-567

Author(s):

K.C. Chan ◽

Q. Chen ◽

L. Liu

Keyword(s):

Metallic Glass ◽

Strain Rate ◽

Bulk Metallic Glass ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Liquid Region ◽

Free Volume Theory ◽

Glass Matrix Composite ◽

Metallic Glass Matrix Composite

The compressive deformation behavior of as-cast Zr55.9Cu18.6Ta8Al7.5Ni10 Bulk Metallic Glass (BMG) composite with micro-scale particles of Ta-rich solid solution embedded in an amorphous matrix was investigated in the supercooled liquid region. It was found that the apparent viscosity of the BMG is dependent on temperature and strain rate. A deviation from a Newtonian behavior was observed at high strain rate and low temperature. The experimental results can be described by a master curve based on a stretched exponential function and the free volume theory. The structural state and the thermal ability of the BMG composite after deformation are also discussed in the paper.

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Effects of Annealing on Enthalpy Recovery and Nanomechanical Behaviors of a La-Based Bulk Metallic Glass

Metals ◽

10.3390/met11040579 ◽

2021 ◽

Vol 11 (4) ◽

pp. 579

Author(s):

Ting Shi ◽

Lanping Huang ◽

Song Li

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Structural Relaxation ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Liquid Region ◽

Nanoindentation Measurement

Structural relaxation and nanomechanical behaviors of La65Al14Ni5Co5Cu9.2Ag1.8 bulk metallic glass (BMG) with a low glass transition temperature during annealing have been investigated by calorimetry and nanoindentation measurement. The enthalpy release of this metallic glass is deduced by annealing near glass transition. When annealed below glass transition temperature for 5 min, the recovered enthalpy increases with annealing temperature and reaches the maximum value at 403 K. After annealed in supercooled liquid region, the recovered enthalpy obviously decreases. For a given annealing at 393 K, the relaxation behaviors of La-based BMG can be well described by the Kohlrausch-Williams-Watts (KWW) function. The hardness, Young’s modulus, and serrated flow are sensitive to structural relaxation of this metallic glass, which can be well explained by the theory of solid-like region and liquid-like region. The decrease of ductility and the enhancement of homogeneity can be ascribed to the transformation from liquid-like region into solid-like region and the reduction of the shear transition zone (STZ).

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