Glass-forming ability and crystallization behavior of Nd60Al10Ni10Cu20−xFex (x = 0, 2, 4) bulk metallic glass with distinct glass transition

We report a new Mg-based bulk metallic glass-forming alloy: Mg65Cu7.5Ni7.5Zn5 Ag5Y10. The alloy exhibits a glass-forming ability significantly stronger than all previously discovered Mg-based glass formers. Fully glassy rods 9 mm in diameter can be obtained by using copper mold casting. The critical cooling rate for glass formation was estimated to be <50 Ks−1. The reduced glass-transition temperature (Trg) of the glass was determined to be 0.59.

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Effect of Compositional Short Range Order on Glass Formation in Binary Metallic System

MRS Proceedings ◽

10.1557/proc-754-cc6.16 ◽

2002 ◽

Vol 754 ◽

Author(s):

Hao Chen ◽

Mahadevan Khantha ◽

Takeshi Egami

Keyword(s):

Glass Transition ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Glass Formation ◽

Short Range ◽

Short Range Order ◽

Glass Forming Ability ◽

Range Order ◽

Dynamics Simulation ◽

Glass Forming

ABSTRACTMolecular Dynamics simulation was carried out to study the glass transition and crystallization in the metal-metalloid binary system with pair-wise potentials. The results show that a repulsive potential between metalloid (small) atoms increases the glass forming ability. The observation is consistent with the recent theory of bulk metallic glass formation through local glass transition and nano-glass formation. The theory predicted that the compositional short-range order (CSRO) prevents the small atom pairing so as to increase the glass forming ability (GFA). The present results demonstrate the important role of CSRO in bulk metallic glass formation.

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Viscosity Measurements of Zr55Cu30Al10Ni5 Supercooled Liquid Alloy under High-Speed Heating Conditions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2071 ◽

2007 ◽

Vol 539-543 ◽

pp. 2071-2076 ◽

Cited By ~ 1

Author(s):

Tohru Yamasaki ◽

S. Maeda ◽

Daisuke Okai ◽

Takeshi Fukami ◽

Yokoyama Yoshihiko ◽

...

Keyword(s):

Glass Transition ◽

Metallic Glass ◽

Heating Rate ◽

Bulk Metallic Glass ◽

Liquid Alloy ◽

High Speed ◽

Supercooled Liquid ◽

Glass Forming Ability ◽

Glass Transition Temperatures ◽

Glass Forming

Viscosity of a Zr55Cu30Al10Ni5 supercooled liquid alloy having bulk metallic glass forming ability has been measured by using a penetration viscometer with a cylindrical probe under high speed heating conditions at rates between 20°C/min and 400°C/min in the temperature range from the glass transition temperatures (Tg) up to above the crystallization temperatures (Tx). The viscosity of the alloy decreased with increasing the heating rate and tended to saturate at the heating rate of 200°C/min and above. Corresponding measurements of the differential thermal calorimetry (DSC) under the high-speed heating conditions have been also done.

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Effects of Si addition on glass-forming ability and crystallization behavior of DyCoAl bulk metallic glass

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.159964 ◽

2021 ◽

pp. 159964

Author(s):

Liliang Shao ◽

Lin Xue ◽

Qianqian Wang ◽

Kaili Ma ◽

Jindu Huang ◽

...

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Crystallization Behavior ◽

Glass Forming Ability ◽

Glass Forming ◽

Si Addition

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Effect of sulfur on the glass-forming ability, phase transformation, and thermal stability of Cu-Zr-Al bulk metallic glass

Acta Materialia ◽

10.1016/j.actamat.2021.116923 ◽

2021 ◽

pp. 116923

Author(s):

Hao-Ran Jiang ◽

Jing-Yi Hu ◽

Nico Neuber ◽

Benedikt Bochtler ◽

Bastian Adam ◽

...

Keyword(s):

Thermal Stability ◽

Phase Transformation ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Glass Forming Ability ◽

Glass Forming ◽

Thermal Stability Of

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Strong Liquid Behavior of Zr-Ti-Cu-Ni-Be Bulk Metallic Glass Forming Alloys

MRS Proceedings ◽

10.1557/proc-455-369 ◽

1996 ◽

Vol 455 ◽

Cited By ~ 26

Author(s):

Ralf Busch ◽

Andreas Masuhr ◽

Eric Bakke ◽

William L. Johnson

Keyword(s):

Glass Transition ◽

Melting Point ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Supercooled Liquid ◽

Glass Transition Region ◽

Glass Forming ◽

Liquid Behavior ◽

Metallic Liquids ◽

Microscopic Origin

ABSTRACTThe viscosities of the Zr46.75Ti8.25Cu7.5Ni10Be27.5 and the Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass forming liquids was determined from the melting point down to the glass transition in the entire temperature range of the supercooled liquid. The temperature dependence of the viscosity in the supercooled liquid obeys the Vogel-Fulcher-Tammann (VFT) relation. The fragility index D is about 20 for both alloys and the ratio between glass transition temperature and VFT temperature is found to be 1.5. A comparison with other glass forming systems shows that these bulk metallic glass formers are strong liquids comparable to sodium silicate glass. Furthermore, they are the strongest among metallic glass forming liquids. This behavior is a main contributing factor to the glass forming ability since it implicates a higher viscosity from the melting point down to the glass transition compared to other metallic liquids. Thus, the kinetics in the supercooled liquid is sluggish and yields a low critical cooling rate for glass formation. The relaxation behavior in the glass transition region of the alloys is consistent with their strong glassy nature as reflected by a stretching exponent that is close to 0.8. The microscopic origin of the strong liquid behavior of bulk metallic glass formers is discussed.

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