Improvement of AlN Thermal Conductivity Based on Reductive Compound Additives

AlN ceramics were prepared by plasma activation sintering (PAS) with compound additives yttrium acetylacetonate (Y(acac) 3 ) and melamine (C 3 H 6 N 6 ). The effects of compound additives on the microstructure, density, and thermal properties of AlN ceramic were studied. Y(acac) 3 and C 3 H 6 N 6 can form Y 2 O 3 , residual organic carbon and reducing gas during the heating process, which improves the AlN sintering performance at a temperature of 1 700 °C and the bulk thermal conductivity. When the content of Y(acac) 3 is 10 wt% and C 3 H 6 N 6 is 3 wt%, the thermal conductivity of AlN ceramics is 105.6 W/(m·K), which is much higher than that of AlN ceramics with Y 2 O 3 under the same sintering conditions. This work provides theoretical reference for the preparation of high-performance AlN ceramic.