Al2O3 ceramics was fabricated by low pressure injection molding and successive normal sintering and HIP sintering. Fine particles of Al₂O₃ with mean particle size of 0.23μm were used as starting
matereal. By adding 17-18 wt% of wax binder Selna E-146 to the powder, ceramic slurry was successfully injected to form an uniform compact.
In normal sintering at 1275°C, sintered specimen showed 99% bulk density. The mean bending strength 71.6kgf/mm2 was obtained in the specimen normally sintered at 1300°C for 3 h.
On the other hand, the specimen HIP sintered at 1300°C for 3 h showed bulk density of 99.7% and the maximum mean bending strength of 81.0kgf/mm². According to SEX observation of fractured surface, grain size of HIP sintered body at 1300°C was 0.5-2.0μm in size and fracture within grain was frequently observed. Bending strength decreases as sintering temperture raises above 1500°C, because of remarked grain growth.