Microstructure of composite YAG crystal/ceramics

Transparent composite YAG crystal/ceramics were synthesized by solid-state reaction method using high-purity Y2O3, Al2O3 powders as raw materials. The mixed slurry was dried, sieved, and cold-isostatically pressed with Nd:YAG crystal under a pressure of 250 MPa. The mixed powder compacts were sintered at 1780 °C for 10 h under vacuum and annealed at 1450 °C for 20 h in air. The microstructure of YAG crystal/ceramics ceramics was studied with SEM and EPMA, which showed there was an intermediate layer between Nd:YAG crystal and YAG ceramics. HRTEM image and corresponding SAED patterns studied showed that the intermediate layer was the YAG ceramics grain that grew along Nd:YAG crystal orientation and has become one part of crystal.