Impact of high pressure on reversible structural relaxation of metallic glass

Abstract

We theoretically investigate the temperature dependence of the reversible structural relaxation time and diffusion constant of metallic glasses under pressure. 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 our numerical results agree well with prior experimental results. An increase of 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 taking the metastable state into account. The presence of external compression is also shown to trigger a fragile-to-strong crossover in metallic glasses.

This paper has been accepted for publication in Physica Status Solidi (RRL) - Rapid Research Letters

References in corpus (3)

• Effects of Cooling Rate on Structural Relaxation in Amorphous Drugs: Elastically Collective Nonlinear Langevin Equation Theory and Machine Learning Study
• Coupling between structural relaxation and diffusion in glass-forming liquids under pressure variation
• Determination of Young's modulus of active pharmaceutical ingredients by relaxation dynamics at elevated pressures

Cited by in corpus (1)

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