Explosive Welding of ZrTiCuNiBe Bulk Metallic Glass to Crystalline Metallic Plates

Recently, a number of amorphous alloys that possess high glass-forming ability and a wide supercooled liquid region before crystallization have been discovered. Especially, bulk metallic glasses, which are made in bulk form with a thickness of ~10 mm at slow cooling rates of the order of 1~100 K/s, have been noted as an industrial application. Hence the welding of bulk metallic glasses to other materials is very important. Explosive welding of most popular Zr41.2Ti13.8Cu10Ni12.5Be22.5 bulk metallic glass to crystalline pure Ti and SUS304 plates is investigated in this paper. The BMGs was found to retain the amorphous structure and the original mechanical properties. The sound bonding with other materials is expected to push forward the application of bulk metallic glass for industrial usage.

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Granulation of Bulk Metallic Glass Forming Alloys as a Feedstock for Thermoplastic Forming and their Compaction into Bulk Samples

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.589 ◽

2016 ◽

Vol 879 ◽

pp. 589-594 ◽

Cited By ~ 2

Author(s):

David Geissler ◽

Jacob Grosse ◽

Sven Donath ◽

David Ehinger ◽

Mihai Stoica ◽

...

Keyword(s):

Metallic Glasses ◽

Shear Bands ◽

Bulk Metallic Glasses ◽

Supercooled Liquid ◽

Amorphous Structure ◽

Supercooled Liquid Region ◽

Structural Defects ◽

Liquid Region ◽

Brittle Behavior ◽

Technological Approach

The various technologically important properties of metallic glasses are intimately connected to their amorphous structure that lacks the archetypical structural defects of polycrystalline metals and alloys, i.e. dislocations and grain boundaries. However, the amorphous structure also limits the application potential of this class of materials because of a macroscopically brittle behavior and size limitations. Consequently, with some exceptions, at least one dimension for technological products is limited to a few millimeters or even less. With the presented technological approach this drawback will be addressed. Our first results on several alloys show that with a dedicated instrumentation amorphous granulates can be successfully produced. By hot pressing in the supercooled liquid region, these granulates can be compacted into bulk shapes in the cm range. Further, due to the low viscosity of the supercooled liquid state, this technology disposes of a high formability. It is demonstrated that not only compact samples but also complex shapes in near net shape geometry can be produced. Results on the mechanical properties and microstructure will be discussed and related to important processing issues. Even though this technological approach does not directly address the second drawback of bulk metallic glasses, i.e. catastrophic failure due to highly localized shear bands, it is believed that this route offers possible pathways to improve this issue as well and, most important, to offer a technological route for implementing bulk metallic glasses into products of rather arbitrary shape and larger size.

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Plasticity in Bulk Metallic Glass Composites Containing Dual Amorphous Phases

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2026 ◽

2007 ◽

Vol 539-543 ◽

pp. 2026-2030 ◽

Cited By ~ 6

Author(s):

J.K. Lee ◽

H.J. Kim ◽

Taek Soo Kim ◽

Jung Chan Bae

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Amorphous Phase ◽

Glass Matrix ◽

Supercooled Liquid ◽

Amorphous Structure ◽

Supercooled Liquid Region ◽

Liquid Region ◽

Glass Composites ◽

Amorphous Phases

Bulk metallic glass (BMG) composites with dual amorphous phases were fabricated by spark plasma sintering of a mixture of Cu-based and Zr-based amorphous powders in their overlapped supercooled liquid region. The Zr-based amorphous phases are well distributed homogeneously in the Cu-based metallic glass matrix after consolidation. The BMG composite still remains as an amorphous structure after consolidation. The BMG composite with dual amorphous phases shows macroscopic plasticity after yielding, and the plastic strain increased to around 3.4% in the BMG composite containing 30 vol% Zr-based amorphous phase. The successful consolidation of BMG composite with enhanced plasticity was achieved by introducing a second amorphous phase in the metallic glass matrix.

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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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