Predicted interfacial thermal conductance and thermal conductivity of graphite flakes/Al composites with different alloy composition

Abstract

Abstract Graphite flake/Al composites are promising thermal management materials due to their light weight and excellent thermal properties. The interface structure is a key factor that impacts the thermophysical properties. In this work, prediction models based on the acoustic mismatch model (AMM) and the effective medium approach (EMA) were developed to evaluate the effect of the alloying elements on the interfacial thermal conductance (ITC) and thermal conductivity (TC) of graphite flake/Al composites. With the increase in Si content, the ITC for the graphite flakes/Al composites increases clearly. In contrast, the ITC for the graphite flakes/Al composites decreases with the increase in Mg content. The variation range of ITC of graphite flakes/Al–Mg–Si composites is (2.3 × 107–3.1 × 107) W m−1 K−1. The thermal conductivity of the graphite flakes/Al–Mg–Si composites is in the range of (412–476) W m−1 K−1. With the increase in the volume fraction of graphite flake, the thermal conductivity of the graphite flakes/Al composites is significantly improved.