The temperature dependence of the reversible structural relaxation time and diffusion constant of metallic glasses under pressure is theoretically investigated. The compression not only changes the glassy dynamics, but also generates a metastable state along with a higher-energy state where the system can rejuvenate. The relaxation times for forward and backward transitions in this two-state system are nearly identical and much faster than the relaxation time without accounting for barrier recrossing. At ambient pressure, the expected irreversible relaxation process is recovered, and the numerical results agree well with prior experimental results. An increase in pressure has a minor effect on the relaxation time and diffusion constant that one computes without considering the influence of the metastable state, but it leads to a large reduction of the reversible relaxation time computed upon considering the metastable state. The presence of external compression is also shown to trigger a fragile-to-strong crossover in metallic glasses.

Impact of High Pressure on Reversible Structural Relaxation of Metallic Glass / N.K. Ngan, A.D. Phan, A. Zaccone. - In: PHYSICA STATUS SOLIDI. RAPID RESEARCH LETTERS. - ISSN 1862-6254. - (2021), pp. 2100235.1-2100235.7. [Epub ahead of print] [10.1002/pssr.202100235]

Impact of High Pressure on Reversible Structural Relaxation of Metallic Glass

A. Zaccone
Ultimo
2021

Abstract

The temperature dependence of the reversible structural relaxation time and diffusion constant of metallic glasses under pressure is theoretically investigated. The compression not only changes the glassy dynamics, but also generates a metastable state along with a higher-energy state where the system can rejuvenate. The relaxation times for forward and backward transitions in this two-state system are nearly identical and much faster than the relaxation time without accounting for barrier recrossing. At ambient pressure, the expected irreversible relaxation process is recovered, and the numerical results agree well with prior experimental results. An increase in pressure has a minor effect on the relaxation time and diffusion constant that one computes without considering the influence of the metastable state, but it leads to a large reduction of the reversible relaxation time computed upon considering the metastable state. The presence of external compression is also shown to trigger a fragile-to-strong crossover in metallic glasses.
compression effects; diffusion; glass transition; mechanical properties; metallic glasses;
Settore FIS/03 - Fisica della Materia
Settore FIS/02 - Fisica Teorica, Modelli e Metodi Matematici
28-mag-2021
Article (author)
File in questo prodotto:
File Dimensione Formato  
The_impact_of_high_pressure_on_reversible_structural_relaxation_of_metallic_glass.pdf

Open Access dal 29/05/2022

Tipologia: Post-print, accepted manuscript ecc. (versione accettata dall'editore)
Dimensione 498.45 kB
Formato Adobe PDF
498.45 kB Adobe PDF Visualizza/Apri
pssr.202100235.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 738.13 kB
Formato Adobe PDF
738.13 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/856934
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 2
social impact