Abstract. Composite material on the base of silicon with boron nitride is considered. Special features of the composite thermal conductivity dependence on volume concentration of the filler are studied experimentally. The results show that at 20°С thermal conductivity changes by a factor of 2,5 from 1,46 W/(m·K) to 4,10 W/(m·K), when BN comprises ≈22 vol.%. An explanation for the obtained results is offered on the grounds of percolation theory and the impact of the filler dispersity on the effective thermal conductivity of the composite. The percolation effect appears to be the stronger, the higher is the difference between the studied characteristic of the filler and the binder; example of model system of paraffin + graphite is presented as an illustration. 

Keywords: thermal conductivity, composite material, filler, binder, BN, percolation threshold, percolation

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