Enhancement of Densification and Thermal Conductivity in AlN Ceramics by Addition of Nano‐Sized Particles

Abstract

The effect of addition of nano‐sized particles on densification and thermal conductivity of AlN ceramics was investigated. The commercially available AlN powder (∼0.9 μm) was mixed with 1.89 mass% nano‐sized AlN particles (<0.1 μm), 3.53 mass% Y 2 O 3 , and 2.0 mass% CaO as sintering aid. The mixture was fired at 1500° and 1600°C in a tungsten resistance furnace under flowing N 2 atmosphere. The results showed that a fully densified specimen was obtained at the lower temperature of 1600°C by addition of nano‐sized particles. The thermal conductivity of the resulting product was 133 W/m°C. The value is much higher than the 52 W/m°C for the sample prepared without adding the nano‐sized AlN powder. This study indicates a strong potential for the use of nano‐sized particles as additives in the densification of AlN ceramics.