Fabrication and properties of highly transparent Li0.07Al2.76O3.64N0.36 ceramics by aqueous gelcasting and two-step preparation.

Highly transparent Li 0.07 Al 2.76 O 3.64 N 0.36 discs (φ 22 × 2.0 mm) and blocks (45 × 40 × 12 mm) were successfully prepared by aqueous gelcasting and two-step preparation. After introducing a small amount of lithium, the lower N1s binding energy and higher intensity of Al–N bonds on the surface of Li 0.07 Al 2.76 O 3.64 N 0.36 powder cause Al–N breakage to be effectively avoided, which inhibits the hydrolysis of powder. Using MAM and MABM as monomers and gelling agents, a stable aqueous suspension with solid loading up to 55 vol% and low viscosity of 83 mPa s was prepared, and the rheological properties and gelating behaviour of the slurries were evaluated. Due to its composition and novel crystalline structure, the Li 0.07 Al 2.76 O 3.64 N 0.36 component presented significantly different performances from γ-AlON. The Vickers hardness reached 15.44 ± 0.34 GPa at a load of 9.8 N, and the in-line transmittance reached ∼84.7% at 3.7 μm. [ABSTRACT FROM AUTHOR]