Thermal conductive behavior of zirconium boride coated by nanoalumina with different mass proportions in epoxy composites

The thermal conductive behavior of Zirconium diboride (ZrB 2 ) coated with different proportions nanoalumina (Al 2 O 3 ) in epoxy composites was investigated by the laser flash experimental and finite element analysis (FEA) methods. The coated ZrB 2 composite particles were categorized into the 3-1, 3-2, 3-3 and 3-4 systems, which corresponded to four different mass ratios of ZrB 2 particles to Al 2 O 3 particles, respectively. It could be found that the coated ZrB 2 composite particles were effective for increasing the thermal conductivity of the filled epoxy composites due to more effective formation of the conductive chain structure in the composites compared to the single-phase particles. In comparison, the system of 3-3 showed the most positive effect on improving the thermal conductive performance of epoxy composites. For composites with a 7 vol% of ZrB 2 /Al 2 O 3 composite particles of 3-3 system, its thermal conductivity was 0.65 W m −1 K −1 , increased by 20% and 79% relative to single-filled composites of ZrB 2 and Al 2 O 3 with same filled content, respectively. The predicted thermal conductive results of Al 2 O 3 coated ZrB 2 particles in epoxy matrix obtained by finite element analysis were in reasonable agreement with the experimental results.