A Novel Processing Route for Alumina/Mullite-Based Refractory Materials

U. Betke1, U. Betke2, V. Reschke2, M. Scheffler2

1 Institute for Industrial Chemistry, 39106 Magdeburg/Germany
2 Otto-von-Guericke-University Magdeburg, Institute for Materials and Joining Technology, 39106 Magdeburg/Germany

Revision 13.01.2016, 01.02.2016

Volume 8, Issue 2, Pages 81 - 85


The paper describes a novel processing method for the manufacturing of alumina/mullite composite materials. It makes use of a dissolution process of aluminium isopropylate and a subsequent, but slow increase of the pH value in the processing solution by stepwise addition and decomposition of urotropine. The pH value increase results in a precipitation of aluminium hydroxide, and in the presence of mullite particles and alumina particles a homogeneous solid body is formed after hydrolysis and drying. While it is not possible to obtain intact samples without alumina addition the combined presence of alumina and mullite particles lead to intact and crack-free parts even after sintering at 1650 °C.


mullite/alumina composite, alumina precipitation


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