Spark plasma sintered AlN-BN composites and its thermal conductivity

Abstract

A series of samples of hexagonal boron nitride-aluminum nitride ceramic composites with different amounts of CaF₂ as sintering aid were prepared by spark plasma sintered at 1700–1850 °C for 5 min. The addition of CaF₂ effectively lowered the sintering temperature and promoted the densification of AlN-BN composites. With the increase of sintering temperature, the density increased, and the contiguity of AlN grains enhanced in AlN-BN composites. Thermal conductivity of AlN-BN composites increased with the increase in CaF₂ content and sintering temperature, and there is a maximum value of 78.6 W·m⁻¹·K⁻¹ when the sample with 3wt% CaF₂ sintered at 1800 °C.

Keywords

AlN-BN composites / thermal conductivity / SPS

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