Crystallization analysis and determination of Avrami exponents during isothermal annealing and the effect of cooling rate on the evolution of the atomic structure of Pd78Si16Cu6 alloy: A molecular dynamics simulation study

Abstract

In this study, molecular dynamics simulations have been carried out to investigate the effect of cooling rate on the atomic structure of the Pd78Si16Cu6 alloy and the isothermal annealing process on the evolution of its glassy structure. It is observed that the atomic structure, glass transition temperature and crystallization temperature of the system are affected significantly by the cooling rate. While the liquid system cooled at slower cooling rates than 1 K/ps transitions to a crystalline structure, a glassy structure is observed for faster cooling rates. The crystallization kinetics of the annealing process are explained by the Johnson, Mehl and Avrami model using Honeycutt–Andersen crystalline-type bonded pairs. The findings show that the system transitions from a metastable phase to a stable crystalline phase during isothermal annealing of the amorphous Pd78Si16Cu6 alloy, and increasing the annealing time for lower temperature increases the thermal stability of the amorphous phase.