Preparation of Aluminum Nitride Ceramics by Aqueous Slip-Casting

Aqueous formulations were developed for slip casting of aluminum nitride (AlN) powder without surface treatment. The hydrolysis reaction was suppressed by preparation of the aqueous slurry with the polymer dispersant mixed under 15°C. The 80mass% slurries with dispersant content of above 0.3mass% showed low viscosity and the AlN powders prepared from these slurries by drying had a low oxygen content. The sintered bodies prepared by the aqueous slip casting retained high density and good thermal conductivity. The thermal conductivity of the AlN sintered body with 5mass% Y2O3 prepared from aqueous processing reached to 177W/(m·K).