Fabrication of transparent Y2O3 ceramics via aqueous gelcasting

Transparent Y2O3 ceramics were successfully prepared via aqueous gelcasting and vacuum sintering. A novel and simple gelling system was employed using a nontoxic and water-soluble copolymer, acting as both a dispersant and a gelling agent in air at room temperature. Surface treatment was carried out by a nucleophilic addition reaction to prevent hydrolysis of Y2O3 powder. The rheological behavior of Y2O3 slurries was evaluated to optimize the dispersant content as well as solids loading. After dried and presintered, the cast bodies were sintered at 1850 °C for 6 h in vacuum. Transparent Y2O3 ceramics were obtained with a homogeneous microstructure and as high as 80.9% in-line transmittance at 1100 nm (1 mm thick).