Dafadar, M H and Das, S and Chakravorty, A K (1998) Effect of water used during gelation on the phase transforamtion of Al2O3-SiO2 gel. Transactions of the Indian Ceramic Society, 57 (5). pp. 121-126. ISSN 0371-750X

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Abstract

Two kinds of Al2O3-SiO2 gels have been synthesized out of aluminium nitrate and tetraethyl orthosilicate. First kind of gel, prepared in excess of hydrolysis agent, e.g. water, does not exhibit 980°C exotherm due to formation of a spinel phase at an earlier temperature. Contrary to the first kind, the second kind of gel prepared in absolute alcohol only and in the absence of moisture develops considerable quantity of mullite directly at 980°C with an exotherm in DTA. Comparative phase transformation sequences by X-ray technique reveal corundum prior to mullitization in first kind of gel. This explains the development of diphasic character of the gel because of the presence of large quantity of water during gelation process.

Item Type:	Article
Subjects:	Engineering Materials
Divisions:	UNSPECIFIED
Depositing User:	Bidhan Chaudhuri
Date Deposited:	13 Jul 2012 12:35
Last Modified:	11 Mar 2014 12:47
URI:	http://cgcri.csircentral.net/id/eprint/1583

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