A simple procedure to prepare spherical α-alumina powders
| Autor: | Zhihong Gan, Hongyu Liu, Guiling Ning, Yuan Lin |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Thermogravimetric analysis
Materials science Mechanical Engineering Condensed Matter Physics law.invention Crystallography Chemical engineering Mechanics of Materials law Transmission electron microscopy Differential thermal analysis Particle Gravimetric analysis General Materials Science Calcination Thermal analysis Sol-gel |
| Zdroj: | Materials Research Bulletin. 44:785-788 |
| ISSN: | 0025-5408 |
| DOI: | 10.1016/j.materresbull.2008.09.018 |
| Popis: | Spherical α-alumina powders were prepared by the controlled hydrolysis of aluminum isopropoxide in a hydrolysis system consisting of octanol and acetonitrile. Diverse solvents to dissolve reactant formed diverse hydrolysis systems and affected particle shape of α-alumina powders. The precursors crystallized to γ-alumina at 1000 °C and converted to α-alumina at 1150 °C without intermediate phases. The particle morphology of precursor was retained after it crystallized to α-alumina. The heating rate influenced the particle shape and the state of agglomeration during calcination process. The thermal properties of the precursors were characterized by thermal gravimetric and differential thermal analysis. X-ray diffraction technique was used to confirm the conversion of crystalline phase of alumina powders from amorphous to α-phase. Transmission electron microscopy was used to investigate the morphologies and size of the precursors and products. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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