Thermal Conductivity of Electric Molding Composites Filled with β-Si_3N_4

New electric molding composites were fabricated with hybridizing epoxy andβ-Si_3N_4 in- stead of silica.The thermal conductivity of composites filled withβ-Si_3N_4 was compared with that co-filled withβ-Si_3N_4 and SiO_2.The results demonstrate that the thermal conductivity of the compos- ite increases obviously with the increasing ofβ-Si_3N_4 content.Thermal conductivity ofβ-Si_3N_4-filled composite is about 3.8 times as large as that of SiO_2-filled one when the additional volume fraction achieves to 50%.Based on the experimental results,the discussion of calculating model for predicting thermal conductivity of composites shows that Agari model is more applicable to predict the ther- mal conductivities ofβ-Si_3N_4 filled andβ-Si_3N_4/SiO_2 co-filled composites.Furthermore,a common expression of Agari model for co-filled composites and its parameters are given.