Predicting temperature dependence of the shear modulus of metallic glasses using calorimetric data

The elastic properties of the Zr50Cu40Ag10 metallic alloy, such as the bulk modulus B, the shear modulus G, the Young’s modulus E and the Poisson’s ratio σ, are investigated by molecular dynamics simulation in the temperature range T=250–2000 K and at an external pressure of p=1.0 bar. It is shown that the liquid–glass transition is accompanied by a considerable increase in the shear modulus G and the Young’s modulus E (by more than 50%). The temperature dependence of the Poisson’s ratio exhibits a sharp fall from typical values for metals of approximately 0.32–0.33 to low values (close to zero), which are characteristic for brittle bulk metallic glasses. Non-monotonic temperature dependence of the longitudinal and transverse sound velocity near the liquid-glass transition is also observed. The glass forming ability of the alloy is evaluated in terms of the fragility index m. Its value is m≈64 for the Zr50Cu40Ag10 metallic glass, which is in a good agreement with the experimental data for the Zr-based metallic glasses.

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Elastic Constants in C-plane of Single Crystal Bi 2Sr 2Ca Cu 208 between 80 K and 260 K

MRS Proceedings ◽

10.1557/proc-193-137 ◽

1990 ◽

Vol 193 ◽

Author(s):

Jin Wu ◽

Yening Wang ◽

Yifeng Yan ◽

Zhongxian Zhao

Keyword(s):

Shear Modulus ◽

Single Crystal ◽

Temperature Dependence ◽

Elastic Constants ◽

Wide Temperature Range ◽

Sound Propagation ◽

Anisotropic Elasticity ◽

Ultrasonic Velocities ◽

Temperature Range

ABSTRACTThe temperature dependence of the in-plane C11 C22. C12 and C66 modes between 80 and 260 K of superconducting crystals of Bi2Sr2Ca1Cu208 have been obtained via the measurements of ultrasonic-velocities. The anisotropic elasticity in the a-b plane of single crystal Bi2 Sr2Ca1Cu2O8 is manifest. The shear modulus of sound propagation along the [110] with the polarization has been also calculated and shows an overall trend of softening over a wide temperature range above Tc. The shear modulus C6 6 shows three obvious softening minima around 240–250 K, 150 K and 100 K.

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Metallic Glasses: A New Approach to the Understanding of the Defect Structure and Physical Properties

Metals ◽

10.3390/met9050605 ◽

2019 ◽

Vol 9 (5) ◽

pp. 605 ◽

Cited By ~ 12

Author(s):

Vitaly Khonik ◽

Nikolai Kobelev

Keyword(s):

Shear Modulus ◽

Physical Properties ◽

Experimental Verification ◽

Metallic Glasses ◽

Structural Relaxation ◽

Defect Structure ◽

Relaxation Phenomena ◽

Volume Changes ◽

New Approach ◽

Heat Effects

The work is devoted to a brief overview of the Interstitialcy Theory (IT) as applied to different relaxation phenomena occurring in metallic glasses upon structural relaxation and crystallization. The basic hypotheses of the IT and their experimental verification are shortly considered. The main focus is given on the interpretation of recent experiments on the heat effects, volume changes and their link with the shear modulus relaxation. The issues related to the development of the IT and its relationship with other models on defects in metallic glasses are discussed.

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Temperature Dependences of the Elastic Constants of Precipitation-Hardened Aluminum Alloys 2014 and 2219

Journal of Engineering Materials and Technology ◽

10.1115/1.3443429 ◽

1977 ◽

Vol 99 (2) ◽

pp. 181-184 ◽

Cited By ~ 12

Author(s):

D. T. Read ◽

H. M. Ledbetter

Keyword(s):

Aluminum Alloys ◽

Shear Modulus ◽

Bulk Modulus ◽

Temperature Dependence ◽

Elastic Properties ◽

Elastic Constants ◽

Ultrasonic Pulse ◽

Young’S Moduli ◽

Temperature Dependences ◽

Sound Velocities

Elastic properties of precipitation-hardened aluminum alloys 2014 and 2219 were studied between 4 and 300 K using ultrasonic pulse techniques. Both the longitudinal and transverse sound velocities were measured. Also reported are the Young’s modulus, shear modulus, bulk modulus, and Poisson’s ratio. For both alloys, the Young’s moduli are about ten percent higher than for unalloyed aluminum, and they increase about ten percent on cooling from 300 to 4 K. All the elastic constants show normal temperature dependence.

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Shear modulus and internal friction hystereses during structural relaxation of metallic glasses based on Pd and Zr in the vicinity of the glass transition range

Physics of the Solid State ◽

10.1134/s1063783415080107 ◽

2015 ◽

Vol 57 (8) ◽

pp. 1574-1578 ◽

Cited By ~ 1

Author(s):

V. A. Khonik ◽

Yu. P. Mitrofanov ◽

A. S. Makarov ◽

G. V. Afonin ◽

A. N. Tsyplakov

Keyword(s):

Glass Transition ◽

Internal Friction ◽

Shear Modulus ◽

Metallic Glasses ◽

Structural Relaxation ◽

Transition Range ◽

Glass Transition Range

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Vitrification decoupling from α-relaxation in a metallic glass

Science Advances ◽

10.1126/sciadv.aay1454 ◽

2020 ◽

Vol 6 (17) ◽

pp. eaay1454

Author(s):

Xavier Monnier ◽

Daniele Cangialosi ◽

Beatrice Ruta ◽

Ralf Busch ◽

Isabella Gallino

Keyword(s):

Metallic Glass ◽

Temperature Dependence ◽

Metallic Glasses ◽

Materials Science ◽

Scanning Calorimetry ◽

Fictive Temperature ◽

Fundamental Properties ◽

Fast Scanning Calorimetry ◽

Arrhenius Temperature Dependence ◽

Arrhenius Temperature

Understanding how glasses form, the so-called vitrification, remains a major challenge in materials science. Here, we study vitrification kinetics, in terms of the limiting fictive temperature, and atomic mobility related to the α-relaxation of an Au-based bulk metallic glass former by fast scanning calorimetry. We show that the time scale of the α-relaxation exhibits super-Arrhenius temperature dependence typical of fragile liquids. In contrast, vitrification kinetics displays milder temperature dependence at moderate undercooling, and thereby, vitrification takes place at temperatures lower than those associated to the α-relaxation. This finding challenges the paradigmatic view based on a one-to-one correlation between vitrification, leading to the glass transition, and the α-relaxation. We provide arguments that at moderate to deep undercooling, other atomic motions, which are not involved in the α-relaxation and that originate from the heterogeneous dynamics in metallic glasses, contribute to vitrification. Implications from the viewpoint of glasses fundamental properties are discussed.

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