Thermal conductivity and dielectric property of hot-pressing sintered AlN–BN ceramic composites

Abstract

A study was conducted of the effects of sintering temperature and CaF 2 additives on densification, microstructure, dielectric property and thermal conductivity of AlN–BN composites. Increasing sintering temperature and CaF 2 contents help to improve the densification, thermal conductivity, and purification of the grain boundaries. Thermal conductivity value reached 110 W m −1 K −1 for AlN–BN composites with 3 wt.% CaF 2 and sintered at 1850 °C. Increasing sintering temperature decreases relative dielectric constant and tan δ . The increase in CaF 2 content increases relative dielectric constant and decreases tan δ . Relative dielectric constants values were between 7.29 and 7.64 and dielectric loss tangent values ranged from 6.36 to 7.83 × 10 −4 at 1 MHz.