Enhancement of thermal percolation in composites: A two-dimensional case study

We investigated the thermal conductivity (TC) of a two-dimensional composite consisting of matrices with low TC and nanowire fillers with high TC using the Monte Carlo method and the finite element method. Compared to the electrical percolation that requires direct contact between fillers, an additional thermal transport channel through non-contact fillers is found to be important for the thermal percolation in composites. This additional channel can lead to an effective expansion of thermal percolation network by including extra fillers into the network. Thus, it can be utilized to enhance the TC of the composite that is helpful to improve the performance of thermal interface materials.