Particular-shaped powders obtained by modification of aluminium and zirconium alkoxides
✍ Scribed by S. Dick; C. Suhr; J.L. Rehspringer; M. Daire
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- English
- Weight
- 482 KB
- Volume
- 109
- Category
- Article
- ISSN
- 0921-5093
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✦ Synopsis
The Al20~-ZrO 2 system is of great interest to structural ceramics thanks to the high tenacity of this kind of diphasic material. From all preparative processes, we have chosen the sol-gel method. This consists of the hydrolysis of metal alkoxides to obtain a sol. Polycondensation reactions then lead to a gel which, after a drying process, gives the final powder.
This work shows that variation of the powder morphology can be induced by modification of the alkoxide. Therefi~re, we have compared these results with those obtained without modification. Concerning acid modification, we have found that the acid/Al(C4H~O)_ ~ ratio influences the powder morphology. In the case of the acid/Al(C4HgO)3 ratio being greater than 2.8 we have obtained a homogeneous population of spherical particles.
The following paper presents a comparative investigation of the ceramics characteristics of these powders: specific area, dilatometric curves, electron microscopy observations and electron microdiffractions are reported.