Tuning β Relaxation via the Glass-To-Glass Transition in a Pseudo-High Entropy Metallic Glass

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Materials Science

Background:

• The glass-to-glass transition is a phase transformation in amorphous materials.
• This transition significantly impacts the structure and properties of metallic glasses.
• The effect of this transition on β relaxation behavior is not well understood.

Purpose of the Study:

• To investigate the influence of the glass-to-glass transition on β relaxation in metallic glasses.
• To characterize the structural and dynamic changes associated with the transition.
• To explore the potential for tuning β relaxation through this transition.

Main Methods:

• Classical molecular dynamics simulations were employed.
• A pseudo-high entropy alloy (Zr65Al7Fe7Co7Ni7Ag7) was studied.
• The study involved heating and isothermal annealing to induce phase transformations.

Main Results:

• The as-cast metallic glass (gA) underwent a glass-to-glass transition around 849 K.
• Isothermal annealing at 900 K transformed gA into a new metallic glass phase (gB).
• gB exhibited a more pronounced β relaxation peak and higher characteristic temperature (Tβ) compared to gA, attributed to increased atomic mobility and altered bonding probabilities.

Conclusions:

• The glass-to-glass transition can be used to modify β relaxation in metallic glasses.
• The gB phase shows enhanced β relaxation due to a higher population of mobile atoms.
• Findings offer a new approach for tailoring metallic glass properties via phase transitions.