Structural relaxation in metallic glasses

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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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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Effects of plastic deformation and hydrogen charging on the internal friction in bulk and ribbon metallic glasses Zr52.5Cu17.9Ni14.6Al10Ti5 and Pd40Cu30Ni10P20

Journal of Materials Research ◽

10.1557/jmr.2007.0049 ◽

2007 ◽

Vol 22 (2) ◽

pp. 274-284

Author(s):

M. Eggers ◽

H.-R. Sinning ◽

V.A. Khonik ◽

H. Neuhäuser

Keyword(s):

Metallic Glasses ◽

Structural Relaxation ◽

Amorphous Structure ◽

Continuous Heating ◽

Hydrogen Charging ◽

Metal Metal ◽

Set Up ◽

Vibrating Reed ◽

Damping Peak ◽

Temperature Time

Two different types of metallic glasses, a metal-metal-based and a metal-metalloid-based one, in both bulk and ribbon form (i.e., produced with very different quenching rates) are compared with respect to their structural relaxation behavior during continuous heating (2 K/min) in a vibrating-reed set-up (frequencies 0.2–5 kHz). The variation of damping as a function of temperature, time, and strain amplitude is shown as a measure of the content of structural relaxation centers, whose nature is studied by means of artificially introduced irregularities into the amorphous structure (i.e., by cold rolling and by hydrogen charging). The results indicate that the hydrogen damping peak, which is only observed in the Zr-based glass, is more probably due to hydrogen reorientation jumps than due to reorientation of hydrogen-related, dislocation-like distortion fields although the latter cannot be ruled out. A pronounced deformation damping peak could not be found in contrast to earlier results in the literature, probably owing to the selected degrees of deformation.

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