Insight into the roles of the glassy phase in glass-ceramics during the cascade collisions

Abstract

A fully fundamental understanding of the roles of the glassy phase (GP) in Glass-Ceramics (GCs) during the cascade collisions remains elusive. In this work, an efficient Molecular dynamics (MD) model with continuous controlled melting and quenching procedures is proposed to mimic the cascade collisions considering the electron stopping effect. Then, the details of both structure evolution and the primary knock-on atom (PKA) behavior induced by the cascade collisions as well as thermal peak effect are observed. The results show that the roles of the GP layer during the cascade collisions can be defined as role I and role II according to the behavior of the PKA. The kinetic energy of the PKA decreases sharply when the PKA passes through the role I. However, the energy exchange between the PKA and the atoms in the GP layer is relatively less and smoother under the role II. Combined with the electron stopping effect and the high energy distorted atoms, the cascade collisions induce a large amount of energy loss in the GP layer. Besides, the distribution of kinetic energy is in good agreement with that of the Frenkel pairs. The mechanism behind the roles of the GP layer is the interaction between the high/low energy distortion atom group and the PKA.