Seeding a mixture of boehmite (AIOOH) and colloidal ZrO2 with α‐alumina particles and sintering at 1400°C for 100 min results in 98% density. The low sintering temperature, relative to conventional powder processing, is a result of the small alumina particle size (∼0.3 μm) obtained during the θ‐to α‐alumina transformation, homogeneous mixing, and the uniform structure of the sol‐gel system. Complete retention of pure ZrO2 in the tetragonal phase was obtained to 14 vol% ZTA because of the low‐temperature sintering. The critical grain size for tetragonal ZrO2 was determined to be ∼0.4 μm for the 14 vol% ZrO2—Al2O3 composite. From these results it is proposed that seeded boehmite gels offer significant advantages for process control and alumina matrix composite fabrication.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of the American Ceramic Society|
|State||Published - Jan 1989|
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Materials Chemistry