Role of electronic thermal transport in amorphous metal recrystallization: a molecular dynamics study

TL;DR

This study uses molecular dynamics coupled with electronic thermal transport modeling to show that electron-phonon interactions significantly influence recrystallization velocity in amorphous metals, aligning simulations more closely with experimental results.

Contribution

It introduces a coupled MD and continuum electronic thermal transport model to study recrystallization, highlighting the impact of electron-phonon coupling on recrystallization dynamics.

Findings

Higher electron-phonon coupling reduces recrystallization velocity.

System size influences initial recrystallization speed.

Including electronic thermal transport improves experimental agreement.

Abstract

Recrystallization of glasses is important in a wide range of applications including electronics and reactive materials. Molecular dynamics (MD) has been used to provide an atomic picture of this process, but prior work has neglected the thermal transport role of electrons, the dominant thermal carrier in metallic systems. We characterize the role of electronic thermal conductivity on the velocity of recrystallization in Ni using MD coupled to a continuum description of electronic thermal transport via a two-temperature model. Our simulations show that for strong enough coupling between electrons and ions, the increased thermal conductivity removes the heat from the exothermic recrystallization process more efficiently, leading to a lower effective temperature at the recrystallization front and, consequently, lower propagation velocity. We characterize how electron-phonon coupling strength and system size affects front propagation velocity. Interestingly, we find that initial recrystallization velocity increases with decreasing in system size due to higher overall temperatures. Overall, we show that a more accurate description of thermal transport due to the incorporation of electrons results in better agreement with experiments.