Energy transport mechanisms and characteristic vibration energy regimes for thermal conduction in bulk metallic glass

Abstract

Bulk metallic glass (BMG) exhibits intriguing physical transport behavior due to its amorphous nature. In this work, by taking a classical BMG material Zr41.2Ti13.8Ni10Cu12.5Be22.5 (Vit1) as the model system, we reveal the impact of structural transition, from a fully amorphous state to a partial and then a completely crystalline state, on the heat and charge transport processes in the temperature range of 4–300 K. We identify the dominant types of energy carriers, which we find change considerably with temperature and structural details. We resolve the contribution of three types of vibrons, namely, propagons, diffusons, and locons, to thermal conduction in the amorphous state and determine their characteristic vibration energy regimes. The present work provides a further understanding of transport behavior of BMG, with important implications for engineering practice at elevated temperatures.