Transformation of boehmite-derived alumina gel to α-Al2O3 in unseeded gels is strongly influenced by the parent phase, θ-Al2O3. In seeded gels the perfect structure of the epitaxial substrate (α-Al2O3, 0.3 wt.%) influences the surrounding defect 0-phase resulting in (a) fewer imperfections due to lower transformation enthalpy to α-Al2O3, and (b) multiple nucleation sites of α-Al2O3 at the α-Al2O3 seed surface. The rate of transformation expressed for the same number of α-Al2O3 nuclei in unseeded and seeded gels indicates that it is faster in the unseeded gel than in the seeded gel.
All Science Journal Classification (ASJC) codes
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering